201
|
Haroon E, Miller AH, Sanacora G. Inflammation, Glutamate, and Glia: A Trio of Trouble in Mood Disorders. Neuropsychopharmacology 2017; 42:193-215. [PMID: 27629368 PMCID: PMC5143501 DOI: 10.1038/npp.2016.199] [Citation(s) in RCA: 328] [Impact Index Per Article: 46.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 09/05/2016] [Accepted: 09/08/2016] [Indexed: 02/07/2023]
Abstract
Increasing data indicate that inflammation and alterations in glutamate neurotransmission are two novel pathways to pathophysiology in mood disorders. The primary goal of this review is to illustrate how these two pathways may converge at the level of the glia to contribute to neuropsychiatric disease. We propose that a combination of failed clearance and exaggerated release of glutamate by glial cells during immune activation leads to glutamate increases and promotes aberrant extrasynaptic signaling through ionotropic and metabotropic glutamate receptors, ultimately resulting in synaptic dysfunction and loss. Furthermore, glutamate diffusion outside the synapse can lead to the loss of synaptic fidelity and specificity of neurotransmission, contributing to circuit dysfunction and behavioral pathology. This review examines the fundamental role of glia in the regulation of glutamate, followed by a description of the impact of inflammation on glial glutamate regulation at the cellular, molecular, and metabolic level. In addition, the role of these effects of inflammation on glia and glutamate in mood disorders will be discussed along with their translational implications.
Collapse
Affiliation(s)
- Ebrahim Haroon
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA
| | - Andrew H Miller
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA
| | - Gerard Sanacora
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| |
Collapse
|
202
|
Tetramethylpyrazine nitrone, a multifunctional neuroprotective agent for ischemic stroke therapy. Sci Rep 2016; 6:37148. [PMID: 27841332 PMCID: PMC5107909 DOI: 10.1038/srep37148] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Accepted: 10/25/2016] [Indexed: 11/08/2022] Open
Abstract
TBN, a novel tetramethylpyrazine derivative armed with a powerful free radical-scavenging nitrone moiety, has been reported to reduce cerebral infarction in rats through multi-functional mechanisms of action. Here we study the therapeutic effects of TBN on non-human primate model of stroke. Thirty male Cynomolgus macaques were subjected to stroke with 4 hours ischemia and then reperfusion. TBN were injected intravenously at 3 or 6 hours after the onset of ischemia. Cerebral infarction was examined by magnetic resonance imaging at 1 and 4 weeks post ischemia. Neurological severity scores were evaluated during 4 weeks observation. At the end of experiment, protein markers associated with the stroke injury and TBN treatment were screened by quantitative proteomics. We found that TBN readily penetrated the blood brain barrier and reached effective therapeutic concentration after intravenous administration. It significantly reduced brain infarction and modestly preserved the neurological function of stroke-affected arm. TBN suppressed over-expression of neuroinflammatory marker vimentin and decreased the numbers of GFAP-positive cells, while reversed down-regulation of myelination-associated protein 2', 3'-cyclic-nucleotide 3'-phosphodiesterase and increased the numbers of NeuN-positive cells in the ipsilateral peri-infarct area. TBN may serve as a promising new clinical candidate for the treatment of ischemic stroke.
Collapse
|
203
|
Shimizu T, Osanai Y, Tanaka KF, Abe M, Natsume R, Sakimura K, Ikenaka K. YAP functions as a mechanotransducer in oligodendrocyte morphogenesis and maturation. Glia 2016; 65:360-374. [PMID: 27807898 DOI: 10.1002/glia.23096] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2016] [Accepted: 10/17/2016] [Indexed: 11/06/2022]
Abstract
Oligodendrocytes (OLs) are myelinating cells of the central nervous system. Recent studies have shown that mechanical factors influence various cell properties. Mechanical stimuli can be transduced into intracellular biochemical signals through mechanosensors and intracellular mechanotransducers, such as YAP. However, the molecular mechanisms underlying mechanical regulation of OLs by YAP remain unknown. We found that OL morphology and interactions between OLs and neuronal axons were affected by knocking down YAP. Mechanical stretching of OL precursor cells induced nuclear YAP accumulation and assembly of focal adhesion, key platforms for mechanotransduction. Shear stress decreased the number of OL processes, whereas a dominant-negative form of YAP suppressed these effects. To investigate the roles of YAP in postnatal OLs in vivo, we constructed a novel YAP knock-in mouse and found that in vivo overexpression of YAP widely affected OL maturation. These results indicate that YAP regulates OL morphology and maturation in response to mechanical factors. GLIA 2017;65:360-374.
Collapse
Affiliation(s)
- Takeshi Shimizu
- Division of Neurobiology and Bioinformatics, National Institute for Physiological Sciences, Okazaki, Aichi, 444-8787, Japan.,Department of Physiological Sciences, School of Life Sciences, SOKENDAI, (The Graduate University for Advanced Studies), Okazaki, Aichi, 444-8585, Japan
| | - Yasuyuki Osanai
- Division of Neurobiology and Bioinformatics, National Institute for Physiological Sciences, Okazaki, Aichi, 444-8787, Japan.,Department of Physiological Sciences, School of Life Sciences, SOKENDAI, (The Graduate University for Advanced Studies), Okazaki, Aichi, 444-8585, Japan
| | - Kenji F Tanaka
- Department of Neuropsychiatry, School of Medicine, Keio University, Tokyo, 160-8582, Japan
| | - Manabu Abe
- Department of Cellular Neurobiology, Brain Research Institute, Niigata University, Niigata, Japan
| | - Rie Natsume
- Department of Cellular Neurobiology, Brain Research Institute, Niigata University, Niigata, Japan
| | - Kenji Sakimura
- Department of Cellular Neurobiology, Brain Research Institute, Niigata University, Niigata, Japan
| | - Kazuhiro Ikenaka
- Division of Neurobiology and Bioinformatics, National Institute for Physiological Sciences, Okazaki, Aichi, 444-8787, Japan.,Department of Physiological Sciences, School of Life Sciences, SOKENDAI, (The Graduate University for Advanced Studies), Okazaki, Aichi, 444-8585, Japan
| |
Collapse
|
204
|
Purger D, Gibson EM, Monje M. Myelin plasticity in the central nervous system. Neuropharmacology 2016; 110:563-573. [DOI: 10.1016/j.neuropharm.2015.08.001] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2015] [Revised: 07/20/2015] [Accepted: 08/01/2015] [Indexed: 12/31/2022]
|
205
|
Puchałowicz K, Baranowska-Bosiacka I, Dziedziejko V, Chlubek D. Purinergic signaling and the functioning of the nervous system cells. Cell Mol Biol Lett 2016; 20:867-918. [PMID: 26618572 DOI: 10.1515/cmble-2015-0050] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Accepted: 10/29/2015] [Indexed: 12/19/2022] Open
Abstract
Purinergic signaling in the nervous system has been the focus of a considerable number of studies since the 1970s. The P2X and P2Y receptors are involved in the initiation of purinergic signaling. They are very abundant in the central and peripheral nervous systems, where they are expressed on the surface of neurons and glial cells--microglia, astrocytes, oligodendrocytes and Schwann cells and the precursors of the latter two. Their ligands--extracellular nucleotides--are released in the physiological state by astrocytes and neurons forming synaptic connections, and are essential for the proper functioning of nervous system cells. Purinergic signaling plays a crucial role in neuromodulation, neurotransmission, myelination in the CNS and PNS, intercellular communication, the regulation of ramified microglia activity, the induction of the response to damaging agents, the modulation of synaptic activity and other glial cells by astrocytes, and the induction of astrogliosis. Understanding these mechanisms and the fact that P2 receptors and their ligands are involved in the pathogenesis of diseases of the nervous system may help in the design of drugs with different and more effective mechanisms of action.
Collapse
|
206
|
N-Cadherin is Involved in Neuronal Activity-Dependent Regulation of Myelinating Capacity of Zebrafish Individual Oligodendrocytes In Vivo. Mol Neurobiol 2016; 54:6917-6930. [PMID: 27771903 DOI: 10.1007/s12035-016-0233-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Accepted: 10/16/2016] [Indexed: 02/07/2023]
Abstract
Stimulating neuronal activity increases myelin sheath formation by individual oligodendrocytes, but how myelination is regulated by neuronal activity in vivo is still not fully understood. While in vitro studies have revealed the important role of N-cadherin in myelination, our understanding in vivo remains quite limited. To obtain the role of N-cadherin during activity-dependent regulation of myelinating capacity of individual oligodendrocytes, we successfully built an in vivo dynamic imaging model of the Mauthner cell at the subcellular structure level in the zebrafish central nervous system. Enhanced green fluorescent protein (EGFP)-tagged N-cadherin was used to visualize the stable accumulations and mobile transports of N-cadherin by single-cell electroporation at the single-cell level. We found that pentylenetetrazol (PTZ) significantly enhanced the accumulation of N-cadherin in Mauthner axons, a response that was paralleled by enhanced sheath number per oligodendrocytes. By offsetting this phenotype using oligopeptide (AHAVD) which blocks the function of N-cadherin, we showed that PTZ regulates myelination in an N-cadherin-dependent manner. What is more, we further suggested that PTZ influences N-cadherin and myelination via a cAMP pathway. Consequently, our data indicated that N-cadherin is involved in neuronal activity-dependent regulation of myelinating capacity of zebrafish individual oligodendrocytes in vivo.
Collapse
|
207
|
Lee HU, Nag S, Blasiak A, Jin Y, Thakor N, Yang IH. Subcellular Optogenetic Stimulation for Activity-Dependent Myelination of Axons in a Novel Microfluidic Compartmentalized Platform. ACS Chem Neurosci 2016; 7:1317-1324. [PMID: 27570883 DOI: 10.1021/acschemneuro.6b00157] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Myelination is governed by neuron-glia communication, which in turn is modulated by neural activity. The exact mechanisms remain elusive. We developed a novel in vitro optogenetic stimulation platform that facilitates subcellular activity induction in hundreds of neurons simultaneously. The light isolation was achieved by creating a biocompatible, light-absorbent, black microfluidic device integrated with a programmable, high-power LED array. The system was applied to a compartmentalized culture of primary neurons whose distal axons were interacting with oligodendrocyte precursor cells. Neural activity was induced along whole neurons or was constrained to cell bodies with proximal axons or distal axons only. All three modes of stimulation promoted oligodendrocyte differentiation and the myelination of axons as evidenced by a decrease in the number of oligodendrocyte precursor cells followed by increases in the number of mature oligodendrocytes and myelin sheath fragments. These results demonstrated the potential of our novel optogenetic stimulation system for the global and focal induction of neural activity in vitro for studying axon myelination.
Collapse
Affiliation(s)
- Hae Ung Lee
- Singapore
Institute for Neurotechnology, National University of Singapore, Singapore 119077
| | - Sudip Nag
- Singapore
Institute for Neurotechnology, National University of Singapore, Singapore 119077
| | - Agata Blasiak
- Singapore
Institute for Neurotechnology, National University of Singapore, Singapore 119077
| | - Yan Jin
- Singapore
Institute for Neurotechnology, National University of Singapore, Singapore 119077
| | - Nitish Thakor
- Singapore
Institute for Neurotechnology, National University of Singapore, Singapore 119077
- Department
of Biomedical Engineering, School of Medicine, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - In Hong Yang
- Singapore
Institute for Neurotechnology, National University of Singapore, Singapore 119077
- Department
of Biomedical Engineering, School of Medicine, Johns Hopkins University, Baltimore, Maryland 21218, United States
| |
Collapse
|
208
|
Felling RJ, Covey MV, Wolujewicz P, Batish M, Levison SW. Astrocyte-produced leukemia inhibitory factor expands the neural stem/progenitor pool following perinatal hypoxia-ischemia. J Neurosci Res 2016; 94:1531-1545. [PMID: 27661001 DOI: 10.1002/jnr.23929] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Revised: 08/30/2016] [Accepted: 08/31/2016] [Indexed: 12/14/2022]
Abstract
Brain injuries, such as cerebral hypoxia-ischemia (H-I), induce a regenerative response from the neural stem/progenitors (NSPs) of the subventricular zone (SVZ); however, the mechanisms that regulate this expansion have not yet been fully elucidated. The Notch- Delta-Serrate-Lag2 (DSL) signaling pathway is considered essential for the maintenance of neural stem cells, but it is not known if it is necessary for the expansion of the NSPs subsequent to perinatal H-I injury. Therefore, the aim of this study was to investigate whether this pathway contributes to NSP expansion in the SVZ after H-I and, if so, to establish whether this pathway is directly induced by H-I or regulated by paracrine factors. Here we report that Notch1 receptor induction and one of its ligands, Delta-like 1, precedes NSP expansion after perinatal H-I in P6 rat pups and that this increase occurs specifically in the most medial cell layers of the SVZ where the stem cells reside. Pharmacologically inhibiting Notch signaling in vivo diminished NSP expansion. With an in vitro model of H-I, Notch1 was not induced directly by hypoxia, but was stimulated by soluble factors, specifically leukemia inhibitory factor, produced by astrocytes within the SVZ. These data confirm the importance both of the Notch-DSL signaling pathway in the expansion of NSPs after H-I and in the role of the support cells in their niche. They further support the body of evidence that indicates that leukemia inhibitory factor is a key injury-induced cytokine that is stimulating the regenerative response of the NSPs. © 2016 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Ryan J Felling
- Departments of Neurology and Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland.,Department of Pharmacology, Physiology and Neuroscience, RBHS-New Jersey Medical School, Newark, New Jersey
| | - Matthew V Covey
- Department of Pharmacology, Physiology and Neuroscience, RBHS-New Jersey Medical School, Newark, New Jersey
| | - Paul Wolujewicz
- Department of Microbiology, Biochemistry and Molecular Genetics, RBHS-New Jersey Medical School, Newark, New Jersey
| | - Mona Batish
- Department of Microbiology, Biochemistry and Molecular Genetics, RBHS-New Jersey Medical School, Newark, New Jersey
| | - Steven W Levison
- Department of Pharmacology, Physiology and Neuroscience, RBHS-New Jersey Medical School, Newark, New Jersey.
| |
Collapse
|
209
|
Cao X, Yao Y, Li T, Cheng Y, Feng W, Shen Y, Li Q, Jiang L, Wu W, Wang J, Sheng J, Feng J, Li C. The Impact of Cognitive Training on Cerebral White Matter in Community-Dwelling Elderly: One-Year Prospective Longitudinal Diffusion Tensor Imaging Study. Sci Rep 2016; 6:33212. [PMID: 27628682 PMCID: PMC5024122 DOI: 10.1038/srep33212] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 08/23/2016] [Indexed: 12/04/2022] Open
Abstract
It has been shown that cognitive training (CogTr) is effective and recuperative for older adults, and can be used to fight against cognitive decline. In this study, we investigated whether behavioural gains from CogTr would extend to white matter (WM) microstructure, and whether training-induced changes in WM integrity would be associated with improvements in cognitive function, using diffusion tensor imaging (DTI). 48 healthy community elderly were either assigned to multi-domain or single-domain CogTr groups to receive 24 sessions over 12 weeks, or to a control group. DTI was performed at both baseline and 12-month follow-up. Positive effects of multi-domain CogTr on long-term changes in DTI indices were found in posterior parietal WM. Participants in the multi-domain group showed a trend of long-term decrease in axial diffusivity (AD) without significant change in fractional anisotropy (FA), mean diffusivity (MD) or radial diffusivity (RD), while those in the control group displayed a significant FA decrease, and an increase in MD and RD. In addition, significant relationships between an improvement in processing speed and changes in RD, MD and AD were found in the multi-domain group. These findings support the hypothesis that plasticity of WM can be modified by CogTr, even in late adulthood.
Collapse
Affiliation(s)
- Xinyi Cao
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Centre, Shanghai Jiao Tong University School of Medicine, Shanghai, 200030, China
| | - Ye Yao
- Institute of Science and Technology for Brain-Inspired Intellegence, Fudan University, Shanghai, 200433, China.,Department of Computer Science, University of Warwick, Coventry CV4 7AL, UK
| | - Ting Li
- Shanghai Changning Mental Health Center, Shanghai, 200335, China
| | - Yan Cheng
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Centre, Shanghai Jiao Tong University School of Medicine, Shanghai, 200030, China
| | - Wei Feng
- Department of Psychiatry, Tongji Hospital of Tongji University, Shanghai, 200065, China
| | - Yuan Shen
- Department of Psychiatry, Tenth People's Hospital of Tongji University, Shanghai, 200072, China
| | - Qingwei Li
- Department of Psychiatry, Tongji Hospital of Tongji University, Shanghai, 200065, China
| | - Lijuan Jiang
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Centre, Shanghai Jiao Tong University School of Medicine, Shanghai, 200030, China
| | - Wenyuan Wu
- Department of Psychiatry, Tongji Hospital of Tongji University, Shanghai, 200065, China
| | - Jijun Wang
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Centre, Shanghai Jiao Tong University School of Medicine, Shanghai, 200030, China
| | - Jianhua Sheng
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Centre, Shanghai Jiao Tong University School of Medicine, Shanghai, 200030, China
| | - Jianfeng Feng
- Institute of Science and Technology for Brain-Inspired Intellegence, Fudan University, Shanghai, 200433, China.,Department of Computer Science, University of Warwick, Coventry CV4 7AL, UK.,Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, 200433, China.,Shanghai Center for Mathematical Sciences, Shanghai, 200433, China
| | - Chunbo Li
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Centre, Shanghai Jiao Tong University School of Medicine, Shanghai, 200030, China.,Brain Science and Technology Research Center, Shanghai Jiao Tong University, Shanghai, 200030, China.,Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Ministry of Education, Shanghai Jiao Tong University, Shanghai, 200030, China
| |
Collapse
|
210
|
Filous AR, Silver J. "Targeting astrocytes in CNS injury and disease: A translational research approach". Prog Neurobiol 2016; 144:173-87. [PMID: 27026202 PMCID: PMC5035184 DOI: 10.1016/j.pneurobio.2016.03.009] [Citation(s) in RCA: 108] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Revised: 02/03/2016] [Accepted: 03/03/2016] [Indexed: 12/31/2022]
Abstract
Astrocytes are a major constituent of the central nervous system. These glia play a major role in regulating blood-brain barrier function, the formation and maintenance of synapses, glutamate uptake, and trophic support for surrounding neurons and glia. Therefore, maintaining the proper functioning of these cells is crucial to survival. Astrocyte defects are associated with a wide variety of neuropathological insults, ranging from neurodegenerative diseases to gliomas. Additionally, injury to the CNS causes drastic changes to astrocytes, often leading to a phenomenon known as reactive astrogliosis. This process is important for protecting the surrounding healthy tissue from the spread of injury, while it also inhibits axonal regeneration and plasticity. Here, we discuss the important roles of astrocytes after injury and in disease, as well as potential therapeutic approaches to restore proper astrocyte functioning.
Collapse
Affiliation(s)
- Angela R Filous
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH 216-368-4615, United States.
| | - Jerry Silver
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH 216-368-4615, United States.
| |
Collapse
|
211
|
Wheeler NA, Fuss B. Extracellular cues influencing oligodendrocyte differentiation and (re)myelination. Exp Neurol 2016; 283:512-30. [PMID: 27016069 PMCID: PMC5010977 DOI: 10.1016/j.expneurol.2016.03.019] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 03/03/2016] [Accepted: 03/18/2016] [Indexed: 02/07/2023]
Abstract
There is an increasing number of neurologic disorders found to be associated with loss and/or dysfunction of the CNS myelin sheath, ranging from the classic demyelinating disease, multiple sclerosis, through CNS injury, to neuropsychiatric diseases. The disabling burden of these diseases has sparked a growing interest in gaining a better understanding of the molecular mechanisms regulating the differentiation of the myelinating cells of the CNS, oligodendrocytes (OLGs), and the process of (re)myelination. In this context, the importance of the extracellular milieu is becoming increasingly recognized. Under pathological conditions, changes in inhibitory as well as permissive/promotional cues are thought to lead to an overall extracellular environment that is obstructive for the regeneration of the myelin sheath. Given the general view that remyelination is, even though limited in human, a natural response to demyelination, targeting pathologically 'dysregulated' extracellular cues and their downstream pathways is regarded as a promising approach toward the enhancement of remyelination by endogenous (or if necessary transplanted) OLG progenitor cells. In this review, we will introduce the extracellular cues that have been implicated in the modulation of (re)myelination. These cues can be soluble, part of the extracellular matrix (ECM) or mediators of cell-cell interactions. Their inhibitory and permissive/promotional roles with regard to remyelination as well as their potential for therapeutic intervention will be discussed.
Collapse
Affiliation(s)
- Natalie A Wheeler
- Department of Anatomy and Neurobiology, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, United States
| | - Babette Fuss
- Department of Anatomy and Neurobiology, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, United States.
| |
Collapse
|
212
|
Goetzl EJ, Mustapic M, Kapogiannis D, Eitan E, Lobach IV, Goetzl L, Schwartz JB, Miller BL. Cargo proteins of plasma astrocyte-derived exosomes in Alzheimer's disease. FASEB J 2016; 30:3853-3859. [PMID: 27511944 DOI: 10.1096/fj.201600756r] [Citation(s) in RCA: 268] [Impact Index Per Article: 33.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 07/27/2016] [Indexed: 01/18/2023]
Abstract
Efficient intercellular transfer of RNAs, proteins, and lipids as protected exosomal cargo has been demonstrated in the CNS, but distinct physiologic and pathologic roles have not been well defined for this pathway. The capacity to isolate immunochemically human plasma neuron-derived exosomes (NDEs), containing neuron-specific cargo, has permitted characterization of CNS-derived exosomes in living humans. Constituents of the amyloid β-peptide (Aβ)42-generating system now are examined in 2 distinct sets of human neural cells by quantification in astrocyte-derived exosomes (ADEs) and NDEs, enriched separately from plasmas of patients with Alzheimer's disease (AD) or frontotemporal dementia (FTD) and matched cognitively normal controls. ADE levels of β-site amyloid precursor protein-cleaving enzyme 1 (BACE-1), γ-secretase, soluble Aβ42, soluble amyloid precursor protein (sAPP)β, sAPPα, glial-derived neurotrophic factor (GDNF), P-T181-tau, and P-S396-tau were significantly (3- to 20-fold) higher than levels in NDEs for patients and controls. BACE-1 levels also were a mean of 7-fold higher in ADEs than in NDEs from cultured rat type-specific neural cells. Levels of BACE-1 and sAPPβ were significantly higher and of GDNF significantly lower in ADEs of patients with AD than in those of controls, but not significantly different in patients with FTD than in controls. Abundant proteins of the Aβ42 peptide-generating system in ADEs may sustain levels in neurons. ADE cargo proteins may be useful for studies of mechanisms of cellular interactions and effects of BACE-1 inhibitors in AD.-Goetzl, E. J., Mustapic, M., Kapogiannis, D., Eitan, E., Lobach, I. V., Goetzl, L., Schwartz, J. B., Miller, B. L. Cargo proteins of plasma astrocyte-derived exosomes in Alzheimer's disease.
Collapse
Affiliation(s)
- Edward J Goetzl
- Department of Medicine, University of California, San Francisco, California, USA; .,Jewish Home of San Francisco, Geriatric Research Center, San Francisco, California, USA
| | - Maja Mustapic
- Laboratory of Neurosciences, National Institutes of Health, National Institute on Aging, Baltimore, Maryland, USA
| | - Dimitrios Kapogiannis
- Laboratory of Neurosciences, National Institutes of Health, National Institute on Aging, Baltimore, Maryland, USA
| | - Erez Eitan
- Laboratory of Neurosciences, National Institutes of Health, National Institute on Aging, Baltimore, Maryland, USA
| | - Irina V Lobach
- Clinical Translational Science Institute, University of California, San Francisco, California, USA
| | - Laura Goetzl
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Temple University, Philadelphia, Pennsylvania, USA
| | - Janice B Schwartz
- Department of Medicine, University of California, San Francisco, California, USA.,Jewish Home of San Francisco, Geriatric Research Center, San Francisco, California, USA.,Department of Bioengineering, University of California, San Francisco, California, USA; and
| | - Bruce L Miller
- Memory and Aging Center, Department of Neurology, University of California, San Francisco, California, USA
| |
Collapse
|
213
|
Filley CM, Fields RD. White matter and cognition: making the connection. J Neurophysiol 2016; 116:2093-2104. [PMID: 27512019 DOI: 10.1152/jn.00221.2016] [Citation(s) in RCA: 249] [Impact Index Per Article: 31.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 08/04/2016] [Indexed: 12/14/2022] Open
Abstract
Whereas the cerebral cortex has long been regarded by neuroscientists as the major locus of cognitive function, the white matter of the brain is increasingly recognized as equally critical for cognition. White matter comprises half of the brain, has expanded more than gray matter in evolution, and forms an indispensable component of distributed neural networks that subserve neurobehavioral operations. White matter tracts mediate the essential connectivity by which human behavior is organized, working in concert with gray matter to enable the extraordinary repertoire of human cognitive capacities. In this review, we present evidence from behavioral neurology that white matter lesions regularly disturb cognition, consider the role of white matter in the physiology of distributed neural networks, develop the hypothesis that white matter dysfunction is relevant to neurodegenerative disorders, including Alzheimer's disease and the newly described entity chronic traumatic encephalopathy, and discuss emerging concepts regarding the prevention and treatment of cognitive dysfunction associated with white matter disorders. Investigation of the role of white matter in cognition has yielded many valuable insights and promises to expand understanding of normal brain structure and function, improve the treatment of many neurobehavioral disorders, and disclose new opportunities for research on many challenging problems facing medicine and society.
Collapse
Affiliation(s)
- Christopher M Filley
- Behavioral Neurology Section, Departments of Neurology and Psychiatry, University of Colorado School of Medicine, Aurora, Colorado; .,Denver Department of Veterans Affairs Medical Center, Denver, Colorado; and
| | - R Douglas Fields
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland
| |
Collapse
|
214
|
Shaw JC, Palliser HK, Dyson RM, Hirst JJ, Berry MJ. Long-term effects of preterm birth on behavior and neurosteroid sensitivity in the guinea pig. Pediatr Res 2016; 80:275-83. [PMID: 27055188 DOI: 10.1038/pr.2016.63] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 01/28/2016] [Indexed: 01/10/2023]
Abstract
BACKGROUND Ex-preterm children and adolescents are at risk of developing late-onset neurodevelopmental and behavioral disorders. The mechanisms by which this happens are poorly understood and relevant animal models are required. METHODS Ex-preterm (delivered at 62 d gestation) and term (spontaneously delivered) juvenile guinea pigs underwent behavioral testing at 25 d corrected postnatal age, with tissues collected at 28 d. Neurodevelopmental markers (myelin basic protein (MBP) and glial fibrillary acidic protein (GFAP)) were analyzed in the hippocampus and subcortical white matter by immunohistochemistry. Gamma-aminobutyric acid A (GABAA) receptor subunit mRNA levels were quantified by reverse transcription polymerase chain reaction (RT-PCR), and salivary cortisol measured by enzyme-linked immunosorbent assay. RESULTS Preterm males travelled greater distances, were mobile for longer, spent more time investigating objects, and approached or interacted with familiar animals more than controls. Myelination and reactive astrocyte coverage was lower in the hippocampus and the subcortical white matter in preterm males. Hippocampal levels of the α5 subunit were also lower in the preterm male brain. Baseline salivary cortisol was higher for preterm males compared to controls. CONCLUSION We conclude that juvenile ex-preterm male guinea pigs exhibit a hyperactive phenotype and feature impaired neurodevelopment, making this a suitable model for future therapeutic studies.
Collapse
Affiliation(s)
- Julia C Shaw
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia.,Hunter Medical Research Institute, Mothers and Babies Research Centre, Newcastle, Australia
| | - Hannah K Palliser
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia.,Hunter Medical Research Institute, Mothers and Babies Research Centre, Newcastle, Australia
| | - Rebecca M Dyson
- Department of Paediatrics, Graduate School of Medicine and IHMRI, University of Wollongong, Wollongong, Australia
| | - Jonathan J Hirst
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia.,Hunter Medical Research Institute, Mothers and Babies Research Centre, Newcastle, Australia
| | - Mary J Berry
- Centre for Translational Physiology, University of Otago, Wellington, New Zealand.,Department of Paediatrics and Child Health, University of Otago, Wellington, New Zealand
| |
Collapse
|
215
|
Christensen PC, Samadi-Bahrami Z, Pavlov V, Stys PK, Moore GRW. Ionotropic glutamate receptor expression in human white matter. Neurosci Lett 2016; 630:1-8. [PMID: 27443784 DOI: 10.1016/j.neulet.2016.07.030] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Revised: 07/14/2016] [Accepted: 07/17/2016] [Indexed: 01/01/2023]
Abstract
Glutamate is the key excitatory neurotransmitter of the central nervous system (CNS). Its role in human grey matter transmission is well understood, but this is less clear in white matter (WM). Ionotropic glutamate receptors (iGluR) are found on both neuronal cell bodies and glia as well as on myelinated axons in rodents, and rodent WM tissue is capable of glutamate release. Thus, rodent WM expresses many of the components of the traditional grey matter neuron-to-neuron synapse, but to date this has not been shown for human WM. We demonstrate the presence of iGluRs in human WM by immunofluorescence employing high-resolution spectral confocal imaging. We found that the obligatory N-methyl-d-aspartic acid (NMDA) receptor subunit GluN1 and the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor subunit GluA4 co-localized with myelin, oligodendroglial cell bodies and processes. Additionally, GluA4 colocalized with axons, often in distinct clusters. These findings may explain why human WM is vulnerable to excitotoxic events following acute insults such as stroke and traumatic brain injury and in more chronic inflammatory conditions such as multiple sclerosis (MS). Further exploration of human WM glutamate signalling could pave the way for developing future therapies modulating the glutamate-mediated damage in these and other CNS disorders.
Collapse
Affiliation(s)
- Pia Crone Christensen
- Hotchkiss Brain Institute, Department of Clinical Neuroscience, University of Calgary, Calgary, Alberta, T2 N 4N1, Canada
| | - Zahra Samadi-Bahrami
- ICORD, (International Collaboration on Repair Discoveries), Department of Pathology and Laboratory Medicine, University of British Columbia, Canada
| | - Vlady Pavlov
- ICORD, (International Collaboration on Repair Discoveries), Department of Pathology and Laboratory Medicine, University of British Columbia, Canada
| | - Peter K Stys
- Hotchkiss Brain Institute, Department of Clinical Neuroscience, University of Calgary, Calgary, Alberta, T2 N 4N1, Canada.
| | - G R Wayne Moore
- ICORD, (International Collaboration on Repair Discoveries), Department of Pathology and Laboratory Medicine, University of British Columbia, Canada
| |
Collapse
|
216
|
Abstract
It has been recently known that not only the presence of inhibitory molecules associated with myelin but also the reduced growth capability of the axons limit mature central nervous system (CNS) axonal regeneration after injury. Conventional axon growth studies are typically conducted using multi-well cell culture plates that are very difficult to use for investigating localized effects of drugs and limited to low throughput. Unfortunately, there is currently no other in vitro tool that allows investigating localized axonal responses to biomolecules in high-throughput for screening potential drugs that might promote axonal growth. We have developed a compartmentalized neuron culture platform enabling localized biomolecular treatments in parallel to axons that are physically and fluidically isolated from their neuronal somata. The 24 axon compartments in the developed platform are designed to perform four sets of six different localized biomolecular treatments simultaneously on a single device. In addition, the novel microfluidic configuration allows culture medium of 24 axon compartments to be replenished altogether by a single aspiration process, making high-throughput drug screening a reality.
Collapse
|
217
|
Domingues HS, Portugal CC, Socodato R, Relvas JB. Oligodendrocyte, Astrocyte, and Microglia Crosstalk in Myelin Development, Damage, and Repair. Front Cell Dev Biol 2016; 4:71. [PMID: 27551677 PMCID: PMC4923166 DOI: 10.3389/fcell.2016.00071] [Citation(s) in RCA: 208] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 06/15/2016] [Indexed: 01/01/2023] Open
Abstract
Oligodendrocytes are the myelinating glia of the central nervous system. Myelination of axons allows rapid saltatory conduction of nerve impulses and contributes to axonal integrity. Devastating neurological deficits caused by demyelinating diseases, such as multiple sclerosis, illustrate well the importance of the process. In this review, we focus on the positive and negative interactions between oligodendrocytes, astrocytes, and microglia during developmental myelination and remyelination. Even though many lines of evidence support a crucial role for glia crosstalk during these processes, the nature of such interactions is often neglected when designing therapeutics for repair of demyelinated lesions. Understanding the cellular and molecular mechanisms underlying glial cell communication and how they influence oligodendrocyte differentiation and myelination is fundamental to uncover novel therapeutic strategies for myelin repair.
Collapse
Affiliation(s)
- Helena S Domingues
- Glial Cell Biology Group, Instituto de Biologia Molecular e Celular, Universidade do PortoPorto, Portugal; Glial Cell Biology Group, Instituto de Investigação e Inovação em Saúde (I3S), Universidade do PortoPorto, Portugal
| | - Camila C Portugal
- Glial Cell Biology Group, Instituto de Biologia Molecular e Celular, Universidade do PortoPorto, Portugal; Glial Cell Biology Group, Instituto de Investigação e Inovação em Saúde (I3S), Universidade do PortoPorto, Portugal
| | - Renato Socodato
- Glial Cell Biology Group, Instituto de Biologia Molecular e Celular, Universidade do PortoPorto, Portugal; Glial Cell Biology Group, Instituto de Investigação e Inovação em Saúde (I3S), Universidade do PortoPorto, Portugal
| | - João B Relvas
- Glial Cell Biology Group, Instituto de Biologia Molecular e Celular, Universidade do PortoPorto, Portugal; Glial Cell Biology Group, Instituto de Investigação e Inovação em Saúde (I3S), Universidade do PortoPorto, Portugal
| |
Collapse
|
218
|
Brain white matter structure and COMT gene are linked to second-language learning in adults. Proc Natl Acad Sci U S A 2016; 113:7249-54. [PMID: 27298360 DOI: 10.1073/pnas.1606602113] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Adult human brains retain the capacity to undergo tissue reorganization during second-language learning. Brain-imaging studies show a relationship between neuroanatomical properties and learning for adults exposed to a second language. However, the role of genetic factors in this relationship has not been investigated. The goal of the current study was twofold: (i) to characterize the relationship between brain white matter fiber-tract properties and second-language immersion using diffusion tensor imaging, and (ii) to determine whether polymorphisms in the catechol-O-methyltransferase (COMT) gene affect the relationship. We recruited incoming Chinese students enrolled in the University of Washington and scanned their brains one time. We measured the diffusion properties of the white matter fiber tracts and correlated them with the number of days each student had been in the immersion program at the time of the brain scan. We found that higher numbers of days in the English immersion program correlated with higher fractional anisotropy and lower radial diffusivity in the right superior longitudinal fasciculus. We show that fractional anisotropy declined once the subjects finished the immersion program. The relationship between brain white matter fiber-tract properties and immersion varied in subjects with different COMT genotypes. Subjects with the Methionine (Met)/Valine (Val) and Val/Val genotypes showed higher fractional anisotropy and lower radial diffusivity during immersion, which reversed immediately after immersion ended, whereas those with the Met/Met genotype did not show these relationships. Statistical modeling revealed that subjects' grades in the language immersion program were best predicted by fractional anisotropy and COMT genotype.
Collapse
|
219
|
Cerebellar Changes in Guinea Pig Offspring Following Suppression of Neurosteroid Synthesis During Late Gestation. THE CEREBELLUM 2016; 16:306-313. [DOI: 10.1007/s12311-016-0802-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
220
|
Dean DC, O'Muircheartaigh J, Dirks H, Travers BG, Adluru N, Alexander AL, Deoni SCL. Mapping an index of the myelin g-ratio in infants using magnetic resonance imaging. Neuroimage 2016; 132:225-237. [PMID: 26908314 PMCID: PMC4851913 DOI: 10.1016/j.neuroimage.2016.02.040] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Revised: 02/07/2016] [Accepted: 02/12/2016] [Indexed: 12/03/2022] Open
Abstract
Optimal myelination of neuronal axons is essential for effective brain and cognitive function. The ratio of the axon diameter to the outer fiber diameter, known as the g-ratio, is a reliable measure to assess axonal myelination and is an important index reflecting the efficiency and maximal conduction velocity of white matter pathways. Although advanced neuroimaging techniques including multicomponent relaxometry (MCR) and diffusion tensor imaging afford insight into the microstructural characteristics of brain tissue, by themselves they do not allow direct analysis of the myelin g-ratio. Here, we show that by combining myelin content information (obtained with mcDESPOT MCR) with neurite density information (obtained through NODDI diffusion imaging) an index of the myelin g-ratio may be estimated. Using this framework, we present the first quantitative study of myelin g-ratio index changes across childhood, examining 18 typically developing children 3months to 7.5years of age. We report a spatio-temporal pattern of maturation that is consistent with histological and developmental MRI studies, as well as theoretical studies of the myelin g-ratio. This work represents the first ever in vivo visualization of the evolution of white matter g-ratio indices throughout early childhood.
Collapse
Affiliation(s)
- Douglas C Dean
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA.
| | | | - Holly Dirks
- Advanced Baby Imaging Lab, Brown University School of Engineering, Providence, RI 02912, USA
| | - Brittany G Travers
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA; Department of Kinesiology, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Nagesh Adluru
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Andrew L Alexander
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA; Department of Psychiatry, University of Wisconsin-Madison, Madison, WI 53719, USA; Department of Medical Physics, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Sean C L Deoni
- Advanced Baby Imaging Lab, Brown University School of Engineering, Providence, RI 02912, USA; Department of Pediatric Radiology, Children's Hospital Colorado, Aurora, CO, USA; Department of Radiology, University of Colorado Denver, Denver, CO, USA
| |
Collapse
|
221
|
Li J, Zhang L, Chu Y, Namaka M, Deng B, Kong J, Bi X. Astrocytes in Oligodendrocyte Lineage Development and White Matter Pathology. Front Cell Neurosci 2016; 10:119. [PMID: 27242432 PMCID: PMC4861901 DOI: 10.3389/fncel.2016.00119] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2016] [Accepted: 04/25/2016] [Indexed: 01/14/2023] Open
Abstract
White matter is primarily composed of myelin and myelinated axons. Structural and functional completeness of myelin is critical for the reliable and efficient transmission of information. White matter injury has been associated with the development of many demyelinating diseases. Despite a variety of scientific advances aimed at promoting re-myelination, their benefit has proven at best to be marginal. Research suggests that the failure of the re-myelination process may be the result of an unfavorable microenvironment. Astrocytes, are the most ample and diverse type of glial cells in central nervous system (CNS) which display multiple functions for the cells of the oligodendrocytes lineage. As such, much attention has recently been drawn to astrocyte function in terms of white matter myelin repair. They are different in white matter from those in gray matter in specific regards to development, morphology, location, protein expression and other supportive functions. During the process of demyelination and re-myelination, the functions of astrocytes are dynamic in that they are able to change functions in accordance to different time points, triggers or reactive pathways resulting in vastly different biologic effects. They have pivotal effects on oligodendrocytes and other cell types in the oligodendrocyte lineage by serving as an energy supplier, a participant of immunological and inflammatory functions, a source of trophic factors and iron and a sustainer of homeostasis. Astrocytic impairment has been shown to be directly linked to the development of neuromyelities optica (NMO). In addition, astroctyes have also been implicated in other white matter conditions such as psychiatric disorders and neurodegenerative diseases such as Alzheimer’s disease (AD), multiple sclerosis (MS) and amyotrophic lateral sclerosis (ALS). Inhibiting specifically detrimental signaling pathways in astrocytes while preserving their beneficial functions may be a promising approach for remyelination strategies. As such, the ability to manipulate astrocyte function represents a novel therapeutic approach that can repair the damaged myelin that is known to occur in a variety of white matter-related disorders.
Collapse
Affiliation(s)
- Jiasi Li
- Department of Neurology, Shanghai Changhai Hospital Shanghai, China
| | - Lei Zhang
- Department of Vascular Surgery, Shanghai Changhai Hospital Shanghai, China
| | - Yongxin Chu
- Department of Vascular Surgery, Affiliated Huai'an Hospital of Xuzhou Medical College Huai'an, China
| | - Michael Namaka
- Faculty of Health Sciences, College of Pharmacy and Medicine, University of Manitoba Winnipeg, MB, Canada
| | - Benqiang Deng
- Department of Neurology, Shanghai Changhai Hospital Shanghai, China
| | - Jiming Kong
- Department of Human Anatomy and Cell Science, University of Manitoba Winnipeg, MB, Canada
| | - Xiaoying Bi
- Department of Neurology, Shanghai Changhai Hospital Shanghai, China
| |
Collapse
|
222
|
Alves-Sampaio A, García-Rama C, Collazos-Castro JE. Biofunctionalized PEDOT-coated microfibers for the treatment of spinal cord injury. Biomaterials 2016; 89:98-113. [DOI: 10.1016/j.biomaterials.2016.02.037] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Revised: 02/11/2016] [Accepted: 02/23/2016] [Indexed: 12/26/2022]
|
223
|
Ashtari M, Zhang H, Cook PA, Cyckowski LL, Shindler KS, Marshall KA, Aravand P, Vossough A, Gee JC, Maguire AM, Baker CI, Bennett J. Plasticity of the human visual system after retinal gene therapy in patients with Leber's congenital amaurosis. Sci Transl Med 2016; 7:296ra110. [PMID: 26180100 DOI: 10.1126/scitranslmed.aaa8791] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Much of our knowledge of the mechanisms underlying plasticity in the visual cortex in response to visual impairment, vision restoration, and environmental interactions comes from animal studies. We evaluated human brain plasticity in a group of patients with Leber's congenital amaurosis (LCA), who regained vision through gene therapy. Using non-invasive multimodal neuroimaging methods, we demonstrated that reversing blindness with gene therapy promoted long-term structural plasticity in the visual pathways emanating from the treated retina of LCA patients. The data revealed improvements and normalization along the visual fibers corresponding to the site of retinal injection of the gene therapy vector carrying the therapeutic gene in the treated eye compared to the visual pathway for the untreated eye of LCA patients. After gene therapy, the primary visual pathways (for example, geniculostriate fibers) in the treated retina were similar to those of sighted control subjects, whereas the primary visual pathways of the untreated retina continued to deteriorate. Our results suggest that visual experience, enhanced by gene therapy, may be responsible for the reorganization and maturation of synaptic connectivity in the visual pathways of the treated eye in LCA patients. The interactions between the eye and the brain enabled improved and sustained long-term visual function in patients with LCA after gene therapy.
Collapse
Affiliation(s)
- Manzar Ashtari
- Center for Advanced Retinal and Ocular Therapeutics, University of Pennsylvania Perelman School of Medicine, 309 Stellar-Chance Labs, 422 Curie Boulevard, Philadelphia, PA 19104, USA. F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA 19014, USA.
| | - Hui Zhang
- Department of Computer Science and Centre for Medical Image Computing, University College London, Gower Street, London WC1E 6BT, UK
| | - Philip A Cook
- Penn Image Computing and Science Laboratory, Department of Radiology, University of Pennsylvania, 3600 Market Street, Philadelphia, PA 19104, USA
| | - Laura L Cyckowski
- Department of Radiology, The Children's Hospital of Philadelphia, Philadelphia, PA 19014, USA
| | - Kenneth S Shindler
- Center for Advanced Retinal and Ocular Therapeutics, University of Pennsylvania Perelman School of Medicine, 309 Stellar-Chance Labs, 422 Curie Boulevard, Philadelphia, PA 19104, USA. F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA 19014, USA
| | - Kathleen A Marshall
- Center for Cellular and Molecular Therapeutics at The Children's Hospital of Philadelphia, Colket Translational Research Building, 3501 Civic Center Boulevard, Philadelphia, PA 19014, USA
| | - Puya Aravand
- Center for Advanced Retinal and Ocular Therapeutics, University of Pennsylvania Perelman School of Medicine, 309 Stellar-Chance Labs, 422 Curie Boulevard, Philadelphia, PA 19104, USA. F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA 19014, USA
| | - Arastoo Vossough
- Department of Radiology, The Children's Hospital of Philadelphia, Philadelphia, PA 19014, USA
| | - James C Gee
- Penn Image Computing and Science Laboratory, Department of Radiology, University of Pennsylvania, 3600 Market Street, Philadelphia, PA 19104, USA
| | - Albert M Maguire
- Center for Advanced Retinal and Ocular Therapeutics, University of Pennsylvania Perelman School of Medicine, 309 Stellar-Chance Labs, 422 Curie Boulevard, Philadelphia, PA 19104, USA. F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA 19014, USA. Center for Cellular and Molecular Therapeutics at The Children's Hospital of Philadelphia, Colket Translational Research Building, 3501 Civic Center Boulevard, Philadelphia, PA 19014, USA
| | - Chris I Baker
- Laboratory of Brain and Cognition, National Institutes of Health, 10 Center Drive, MSC 1240, Bethesda, MD 20892, USA
| | - Jean Bennett
- Center for Advanced Retinal and Ocular Therapeutics, University of Pennsylvania Perelman School of Medicine, 309 Stellar-Chance Labs, 422 Curie Boulevard, Philadelphia, PA 19104, USA. F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA 19014, USA. Center for Cellular and Molecular Therapeutics at The Children's Hospital of Philadelphia, Colket Translational Research Building, 3501 Civic Center Boulevard, Philadelphia, PA 19014, USA
| |
Collapse
|
224
|
Lariosa-Willingham KD, Rosler ES, Tung JS, Dugas JC, Collins TL, Leonoudakis D. Development of a central nervous system axonal myelination assay for high throughput screening. BMC Neurosci 2016; 17:16. [PMID: 27103572 PMCID: PMC4840960 DOI: 10.1186/s12868-016-0250-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 04/12/2016] [Indexed: 12/04/2022] Open
Abstract
Background Regeneration of new myelin is impaired in persistent multiple sclerosis (MS) lesions, leaving neurons unable to function properly and subject to further degeneration. Current MS therapies attempt to ameliorate autoimmune-mediated demyelination, but none directly promote the regeneration of lost and damaged myelin of the central nervous system (CNS). Development of new drugs that stimulate remyelination has been hampered by the inability to evaluate axonal myelination in a rapid CNS culture system. Results We established a high throughput cell-based assay to identify compounds that promote myelination. Culture methods were developed for initiating myelination in vitro using primary embryonic rat cortical cells. We developed an immunofluorescent phenotypic image analysis method to quantify the morphological alignment of myelin characteristic of the initiation of myelination. Using γ-secretase inhibitors as promoters of myelination, the optimal growth, time course and compound treatment conditions were established in a 96 well plate format. We have characterized the cortical myelination assay by evaluating the cellular composition of the cultures and expression of markers of differentiation over the time course of the assay. We have validated the assay scalability and consistency by screening the NIH clinical collection library of 727 compounds and identified ten compounds that promote myelination. Half maximal effective concentration (EC50) values for these compounds were determined to rank them according to potency. Conclusions We have designed the first high capacity in vitro assay that assesses myelination of live axons. This assay will be ideal for screening large compound libraries to identify new drugs that stimulate myelination. Identification of agents capable of promoting the myelination of axons will likely lead to the development of new therapeutics for MS patients. Electronic supplementary material The online version of this article (doi:10.1186/s12868-016-0250-2) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Karen D Lariosa-Willingham
- Translational Medicine Center, Myelin Repair Foundation, Sunnyvale, CA, 94085, USA.,Teva Pharmaceuticals, Biologics and CNS Discovery, Redwood City, CA, 94063, USA
| | - Elen S Rosler
- Translational Medicine Center, Myelin Repair Foundation, Sunnyvale, CA, 94085, USA.,Alios BioPharma, South San Francisco, CA, 94080, USA
| | - Jay S Tung
- Translational Medicine Center, Myelin Repair Foundation, Sunnyvale, CA, 94085, USA
| | - Jason C Dugas
- Translational Medicine Center, Myelin Repair Foundation, Sunnyvale, CA, 94085, USA.,Rigel Pharmaceuticals, South San Francisco, CA, 94080, USA
| | - Tassie L Collins
- Translational Medicine Center, Myelin Repair Foundation, Sunnyvale, CA, 94085, USA.,NGM Biopharmaceuticals, Inc., South San Francisco, CA, 94080, USA
| | - Dmitri Leonoudakis
- Translational Medicine Center, Myelin Repair Foundation, Sunnyvale, CA, 94085, USA. .,Teva Pharmaceuticals, Biologics and CNS Discovery, Redwood City, CA, 94063, USA.
| |
Collapse
|
225
|
Activity-Dependent and Experience-Driven Myelination Provide New Directions for the Management of Multiple Sclerosis. Trends Neurosci 2016; 39:356-365. [PMID: 27113322 DOI: 10.1016/j.tins.2016.04.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 03/26/2016] [Accepted: 04/04/2016] [Indexed: 11/20/2022]
Abstract
Despite an appreciation of the importance of myelination and the consequences of pathological demyelination, the fundamental mechanisms regulating myelination are only now being resolved. Neuronal activity has long been considered a plausible regulatory signal for myelination. However, controversy surrounding its dispensability in certain contexts and the difficulty in determining to what degree it influences myelination has limited its widespread acceptance. Recent studies have shed new light on the role of neuronal activity in regulating oligodendrogenesis and myelination. Further, the dynamics of myelin in adulthood and the association between skilled learning and myelination have become increasingly well characterized. These advances present new considerations for the management of multiple sclerosis and open up new approaches to facilitate remyelination following pathological demyelination.
Collapse
|
226
|
Glial progenitor cell migration promotes CNS axon growth on functionalized electroconducting microfibers. Acta Biomater 2016; 35:42-56. [PMID: 26884276 DOI: 10.1016/j.actbio.2016.02.023] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Revised: 01/25/2016] [Accepted: 02/12/2016] [Indexed: 12/20/2022]
Abstract
Electroactive systems that promote directional axonal growth and migration of glial progenitor cells (GPC) are needed for the treatment of neurological injuries. We report the functionalization of electroconducting microfibers with multiple biomolecules that synergistically stimulate the proliferation and migration of GPC, which in turn induce axonal elongation from embryonic cerebral cortex neurons. PEDOT doped with poly[(4-styrenesulfonic acid)-co-(maleic acid)] was synthesized on carbon microfibers and used for covalent attachment of molecules to the electroactive surface. The molecular complexes that promoted GPC proliferation and migration, followed by axonal extension, were composed of polylysine, heparin, basic fibroblast growth factor (bFGF), and matricellular proteins; the combination of bFGF with vitronectin or fibronectin being indispensable for sustained glial and axonal growth. The rate of glial-induced axonal elongation was about threefold that of axons growing directly on microfibers functionalized with polylysine alone. Electrical stimuli applied through the microfibers released bFGF and fibronectin from the polymer surface, consequently reducing GPC proliferation and promoting their differentiation into astrocytes, without causing cell detachment or toxicity. These results suggest that functionalized electroactive microfibers may provide a multifunctional tool for controlling neuron-glia interactions and enhancing neural repair. STATEMENT OF SIGNIFICANCE We report a multiple surface functionalization strategy for electroconducting microfibers (MFs), in order to promote proliferation and guided migration of glial precursor cells (GPC) and consequently create a permissive substrate for elongation of central nervous system (CNS) axons. GPC divided and migrated extensively on the functionalized MFs, leading to fast elongation of embryonic cerebral cortex axons. The application of electric pulses thorough the MFs controlled glial cell division and differentiation. The functionalized MFs provide an advanced tool for neural tissue engineering and for controlling neuron-glial interactions. CNS axonal growth associated to migratory glial precursors, together with the possibility of directing glial differentiation by electrical stimuli applied through the MFs, open a new research avenue to explore for CNS repair.
Collapse
|
227
|
Egawa N, Lok J, Arai K. Mechanisms of cellular plasticity in cerebral perivascular region. PROGRESS IN BRAIN RESEARCH 2016; 225:183-200. [PMID: 27130416 DOI: 10.1016/bs.pbr.2016.03.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Brain vasculature acts in synergism with neurons to maintain brain function. This neurovascular coupling, or trophic coupling between cerebral endothelium and neuron, is now well accepted as a marker for mapping brain activity. Neurovascular coupling is most active in the perivascular region, in which there are ample opportunities for cell-cell interactions within the neurovascular unit. This trophic coupling between cells maintains neurovascular function and cellular plasticity. Recent studies have revealed that even adult brains contain multiple stem cells of various lineages, which may provide cellular plasticity through the process of differentiation among these stem cell populations. In this chapter, we provide an overview of the process by which neurovascular components contribute to cellular plasticity in the cerebral perivascular regions, focusing on mechanisms of cell-cell interaction in adult brain.
Collapse
Affiliation(s)
- N Egawa
- Neuroprotection Research Laboratory, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States
| | - J Lok
- Neuroprotection Research Laboratory, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States; Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States
| | - K Arai
- Neuroprotection Research Laboratory, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States.
| |
Collapse
|
228
|
Steelman AJ, Zhou Y, Koito H, Kim S, Payne HR, Lu QR, Li J. Activation of oligodendroglial Stat3 is required for efficient remyelination. Neurobiol Dis 2016; 91:336-46. [PMID: 27060559 DOI: 10.1016/j.nbd.2016.03.023] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Revised: 03/11/2016] [Accepted: 03/30/2016] [Indexed: 01/26/2023] Open
Abstract
Multiple sclerosis is the most prevalent demyelinating disease of the central nervous system (CNS) and is histologically characterized by perivascular demyelination as well as neurodegeneration. While the degree of axonal damage is correlated with clinical disability, it is believed that remyelination can protect axons from degeneration and slow disease progression. Therefore, understanding the intricacies associated with myelination and remyelination may lead to therapeutics that can enhance the remyelination process and slow axon degeneration and loss of function. Ciliary neurotrophic factor (CNTF) family cytokines such as leukemia inhibitory factor (LIF) and interleukin 11 (IL-11) are known to promote oligodendrocyte maturation and remyelination in experimental models of demyelination. Because CNTF family member binding to the gp130 receptor results in activation of the JAK2/Stat3 pathway we investigated the necessity of oligodendroglial Stat3 in transducing the signal required for myelination and remyelination. We found that Stat3 activation in the CNS coincides with myelination during development. Stimulation of oligodendrocyte precursor cells (OPCs) with CNTF or LIF promoted OPC survival and final differentiation, which was completely abolished by pharmacologic blockade of Stat3 activation with JAK2 inhibitor. Similarly, genetic ablation of Stat3 in oligodendrocyte lineage cells prevented CNTF-induced OPC differentiation in culture. In vivo, while oligodendroglial Stat3 signaling appears to be dispensable for developmental CNS myelination, it is required for oligodendrocyte regeneration and efficient remyelination after toxin-induced focal demyelination in the adult brain. Our data suggest a critical function for oligodendroglial Stat3 signaling in myelin repair.
Collapse
Affiliation(s)
- Andrew J Steelman
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine & Biomedical Sciences, United States; Institute for Neuroscience, Texas A&M University, College Station, TX 77843, United States
| | - Yun Zhou
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine & Biomedical Sciences, United States
| | - Hisami Koito
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine & Biomedical Sciences, United States
| | - SunJa Kim
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine & Biomedical Sciences, United States; Institute for Neuroscience, Texas A&M University, College Station, TX 77843, United States
| | - H Ross Payne
- Department of Veterinary Pathobiology, College of Veterinary Medicine & Biomedical Sciences, United States
| | - Q Richard Lu
- Department of Pediatrics, Brain Tumor Center, Cincinnati Children's Hospital Medical Center, United States
| | - Jianrong Li
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine & Biomedical Sciences, United States; Institute for Neuroscience, Texas A&M University, College Station, TX 77843, United States.
| |
Collapse
|
229
|
Seidl AH, Rubel EW. Systematic and differential myelination of axon collaterals in the mammalian auditory brainstem. Glia 2016; 64:487-94. [PMID: 26556176 PMCID: PMC4752408 DOI: 10.1002/glia.22941] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 10/20/2015] [Indexed: 12/19/2022]
Abstract
A brainstem circuit for encoding the spatial location of sounds involves neurons in the cochlear nucleus that project to medial superior olivary (MSO) neurons on both sides of the brain via a single bifurcating axon. Neurons in MSO act as coincidence detectors, responding optimally when signals from the two ears arrive within a few microseconds. To achieve this, transmission of signals along the contralateral collateral must be faster than transmission of the same signals along the ipsilateral collateral. We demonstrate that this is achieved by differential regulation of myelination and axon caliber along the ipsilateral and contralateral branches of single axons; ipsilateral axon branches have shorter internode lengths and smaller caliber than contralateral branches. The myelination difference is established prior to the onset of hearing. We conclude that this differential myelination and axon caliber requires local interactions between axon collaterals and surrounding oligodendrocytes on the two sides of the brainstem.
Collapse
Affiliation(s)
- Armin H. Seidl
- Virginia Merrill Bloedel Hearing Research Center, University of Washington, Seattle, WA
- Department of Neurology, University of Washington, Seattle, WA
| | - Edwin W Rubel
- Virginia Merrill Bloedel Hearing Research Center, University of Washington, Seattle, WA
- Department of Otolaryngology – Head & Neck Surgery, University of Washington, Seattle, WA
| |
Collapse
|
230
|
Mironova YA, Lenk GM, Lin JP, Lee SJ, Twiss JL, Vaccari I, Bolino A, Havton LA, Min SH, Abrams CS, Shrager P, Meisler MH, Giger RJ. PI(3,5)P2 biosynthesis regulates oligodendrocyte differentiation by intrinsic and extrinsic mechanisms. eLife 2016; 5. [PMID: 27008179 PMCID: PMC4889328 DOI: 10.7554/elife.13023] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Accepted: 03/23/2016] [Indexed: 12/18/2022] Open
Abstract
Proper development of the CNS axon-glia unit requires bi-directional communication between axons and oligodendrocytes (OLs). We show that the signaling lipid phosphatidylinositol-3,5-bisphosphate [PI(3,5)P2] is required in neurons and in OLs for normal CNS myelination. In mice, mutations of Fig4, Pikfyve or Vac14, encoding key components of the PI(3,5)P2 biosynthetic complex, each lead to impaired OL maturation, severe CNS hypomyelination and delayed propagation of compound action potentials. Primary OLs deficient in Fig4 accumulate large LAMP1+ and Rab7+ vesicular structures and exhibit reduced membrane sheet expansion. PI(3,5)P2 deficiency leads to accumulation of myelin-associated glycoprotein (MAG) in LAMP1+perinuclear vesicles that fail to migrate to the nascent myelin sheet. Live-cell imaging of OLs after genetic or pharmacological inhibition of PI(3,5)P2 synthesis revealed impaired trafficking of plasma membrane-derived MAG through the endolysosomal system in primary cells and brain tissue. Collectively, our studies identify PI(3,5)P2 as a key regulator of myelin membrane trafficking and myelinogenesis. DOI:http://dx.doi.org/10.7554/eLife.13023.001 Neurons communicate with each other through long cable-like extensions called axons. An insulating sheath called myelin (or white matter) surrounds each axon, and allows electrical impulses to travel more quickly. Cells in the brain called oligodendrocytes produce myelin. If the myelin sheath is not properly formed during development, or is damaged by injury or disease, the consequences can include paralysis, impaired thought, and loss of vision. Oligodendrocytes have complex shapes, and each can generate myelin for as many as 50 axons. Oligodendrocytes produce the building blocks of myelin inside their cell bodies, by following instructions encoded by genes within the nucleus. However, the signals that regulate the trafficking of these components to the myelin sheath are poorly understood. Mironova et al. set out to determine whether signaling molecules called phosphoinositides help oligodendrocytes to mature and move myelin building blocks from the cell bodies to remote contact points with axons. Genetic techniques were used to manipulate an enzyme complex in mice that controls the production and turnover of a phosphoinositide called PI(3,5)P2. Mironova et al. found that reducing the levels of PI(3,5)P2 in oligodendrocytes caused the trafficking of certain myelin building blocks to stall. Key myelin components instead accumulated inside bubble-like structures near the oligodendrocyte’s cell body. This showed that PI(3,5)P2 in oligodendrocytes is essential for generating myelin. Further experiments then revealed that reducing PI(3,5)P2 in the neurons themselves indirectly prevented the oligodendrocytes from maturing. This suggests that PI(3,5)P2 also takes part in communication between axons and oligodendrocytes during development of the myelin sheath. A key next step will be to identify the regulatory mechanisms that control the production of PI(3,5)P2 in oligodendrocytes and neurons. Future studies could also explore what PI(3,5)P2 acts upon inside the axons, and which signaling molecules support the maturation of oligodendrocytes. Finally, it remains unclear whether PI(3,5)P2signaling is also required for stabilizing mature myelin, and for repairing myelin after injury in the adult brain. Further work could therefore address these questions as well. DOI:http://dx.doi.org/10.7554/eLife.13023.002
Collapse
Affiliation(s)
- Yevgeniya A Mironova
- Department of Cell and Developmental Biology, University of Michigan School of Medicine, Ann Arbor, United States.,Cellular and Molecular Biology Graduate Program, University of Michigan School of Medicine, Ann Arbor, United States
| | - Guy M Lenk
- Department of Human Genetics, University of Michigan School of Medicine, Ann Arbor, United States
| | - Jing-Ping Lin
- Department of Cell and Developmental Biology, University of Michigan School of Medicine, Ann Arbor, United States
| | - Seung Joon Lee
- Department of Biological Sciences, University of South Carolina, Columbia, United States
| | - Jeffery L Twiss
- Department of Biological Sciences, University of South Carolina, Columbia, United States
| | - Ilaria Vaccari
- Human Inherited Neuropathies Unit, INSPE-Institute for Experimental Neurology, San Raffaele Scientific Institute, Milan, Italy
| | - Alessandra Bolino
- Human Inherited Neuropathies Unit, INSPE-Institute for Experimental Neurology, San Raffaele Scientific Institute, Milan, Italy
| | - Leif A Havton
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, United States
| | - Sang H Min
- Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia, United States
| | - Charles S Abrams
- Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia, United States
| | - Peter Shrager
- Department of Neurobiology and Anatomy, University of Rochester Medical Center, Rochester, United States
| | - Miriam H Meisler
- Department of Human Genetics, University of Michigan School of Medicine, Ann Arbor, United States.,Department of Neurology, University of Michigan School of Medicine, Ann Arbor, United States
| | - Roman J Giger
- Department of Cell and Developmental Biology, University of Michigan School of Medicine, Ann Arbor, United States.,Department of Neurology, University of Michigan School of Medicine, Ann Arbor, United States
| |
Collapse
|
231
|
Kıray H, Lindsay SL, Hosseinzadeh S, Barnett SC. The multifaceted role of astrocytes in regulating myelination. Exp Neurol 2016; 283:541-9. [PMID: 26988764 PMCID: PMC5019113 DOI: 10.1016/j.expneurol.2016.03.009] [Citation(s) in RCA: 121] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 03/01/2016] [Accepted: 03/08/2016] [Indexed: 11/29/2022]
Abstract
Astrocytes are the major glial cell of the central nervous system (CNS), providing both metabolic and physical support to other neural cells. After injury, astrocytes become reactive and express a continuum of phenotypes which may be supportive or inhibitory to CNS repair. This review will focus on the ability of astrocytes to influence myelination in the context of specific secreted factors, cytokines and other neural cell targets within the CNS. In particular, we focus on how astrocytes provide energy and cholesterol to neurons, influence synaptogenesis, affect oligodendrocyte biology and instigate cross-talk between the many cellular components of the CNS.
Collapse
Affiliation(s)
- Hülya Kıray
- Institute of Infection, Inflammation and Immunity, Sir Graeme Davies Building, Glasgow Biomedical Research Centre, 120 University Place, University of Glasgow, Glasgow G12 8TA, United Kingdom
| | - Susan L Lindsay
- Institute of Infection, Inflammation and Immunity, Sir Graeme Davies Building, Glasgow Biomedical Research Centre, 120 University Place, University of Glasgow, Glasgow G12 8TA, United Kingdom
| | - Sara Hosseinzadeh
- Institute of Infection, Inflammation and Immunity, Sir Graeme Davies Building, Glasgow Biomedical Research Centre, 120 University Place, University of Glasgow, Glasgow G12 8TA, United Kingdom
| | - Susan C Barnett
- Institute of Infection, Inflammation and Immunity, Sir Graeme Davies Building, Glasgow Biomedical Research Centre, 120 University Place, University of Glasgow, Glasgow G12 8TA, United Kingdom..
| |
Collapse
|
232
|
Mitew S, Xing YL, Merson TD. Axonal activity-dependent myelination in development: Insights for myelin repair. J Chem Neuroanat 2016; 76:2-8. [PMID: 26968658 DOI: 10.1016/j.jchemneu.2016.03.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Revised: 03/01/2016] [Accepted: 03/07/2016] [Indexed: 12/20/2022]
Abstract
Recent advances in transgenic tools have allowed us to peek into the earliest stages of vertebrate development to study axon-glial communication in the control of peri-natal myelination. The emerging role of neuronal activity in regulating oligodendrocyte progenitor cell behavior during developmental myelination has opened up an exciting possibility-a role for neuronal activity in the early stages of remyelination. Recent work from our laboratory and others has also shown that contrary to previously established dogma in the field, complete remyelination up to pre-demyelination levels can be achieved in mouse models of MS by oligodendrogenic neural precursor cells that derive from the adult subventricular zone. These cells are electrically active and can be depolarized, suggesting that neuronal activity may have a modulatory role in their development and remyelination potential. In this review, we summarize recent advances in our understanding of the development of axon-glia communication and apply those same concepts to remyelination, with an emphasis on the particular roles of different sources of oligodendrocyte progenitor cells.
Collapse
Affiliation(s)
- Stanislaw Mitew
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, Victoria, Australia
| | - Yao Lulu Xing
- The Florey Institute of Neuroscience and Mental Health, Parkville, Victoria, Australia
| | - Tobias D Merson
- The Florey Institute of Neuroscience and Mental Health, Parkville, Victoria, Australia; Florey Department of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia.
| |
Collapse
|
233
|
Roe C. Unwrapping Neurotrophic Cytokines and Histone Modification. Cell Mol Neurobiol 2016; 37:1-4. [PMID: 26935061 PMCID: PMC5226993 DOI: 10.1007/s10571-016-0330-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 01/08/2016] [Indexed: 10/25/2022]
Abstract
The conventional view that neuroinflammatory lesions contain strictly pro- and anti-inflammatory cytokines is being challenged. Some proinflammatory products e.g. TNF-α are crucial intermediates in axon regeneration, oligodendroglial renewal and remyelination. A more functional system of nomenclature classifies cytokines by their neuro 'protective' or 'suppressive' properties. Beyond the balance of these 'environmental' or 'extrinsic' signals, specific 'intrinsic' determinants of cytokine signalling appear to influence the outcome of axoglial regeneration. In this commentary, we examine the potential importance of cytokine-induced histone modification on oligodendrocyte differentiation. Neuroinflammation mediates the release of astrocytic leukaemia inhibitory factor (LIF) and erythropoietin (EPO) which potentiates oligodendrocyte differentiation and myelin production. Meanwhile, histone deacetylation strongly suppresses important inhibitors of oligodendrocyte differentiation. Given that LIF and EPO induce histone deacetylases in other systems, future studies should examine whether this mechanism significantly influences the outcome of cytokine-induced remyelination, and whether epigenetic drug targets could potentiate the effects of exogenous cytokine therapy.
Collapse
Affiliation(s)
- Cieron Roe
- Brighton and Sussex Medical School, The Audrey Emerton Building, Eastern Road, Kemp Town, Brighton, BN2 5BE, UK.
| |
Collapse
|
234
|
Olmos-Serrano JL, Kang HJ, Tyler WA, Silbereis JC, Cheng F, Zhu Y, Pletikos M, Jankovic-Rapan L, Cramer NP, Galdzicki Z, Goodliffe J, Peters A, Sethares C, Delalle I, Golden JA, Haydar TF, Sestan N. Down Syndrome Developmental Brain Transcriptome Reveals Defective Oligodendrocyte Differentiation and Myelination. Neuron 2016; 89:1208-1222. [PMID: 26924435 DOI: 10.1016/j.neuron.2016.01.042] [Citation(s) in RCA: 155] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Revised: 11/24/2015] [Accepted: 01/21/2016] [Indexed: 11/18/2022]
Abstract
Trisomy 21, or Down syndrome (DS), is the most common genetic cause of developmental delay and intellectual disability. To gain insight into the underlying molecular and cellular pathogenesis, we conducted a multi-region transcriptome analysis of DS and euploid control brains spanning from mid-fetal development to adulthood. We found genome-wide alterations in the expression of a large number of genes, many of which exhibited temporal and spatial specificity and were associated with distinct biological processes. In particular, we uncovered co-dysregulation of genes associated with oligodendrocyte differentiation and myelination that were validated via cross-species comparison to Ts65Dn trisomy mice. Furthermore, we show that hypomyelination present in Ts65Dn mice is in part due to cell-autonomous effects of trisomy on oligodendrocyte differentiation and results in slower neocortical action potential transmission. Together, these results identify defects in white matter development and function in DS, and they provide a transcriptional framework for further investigating DS neuropathogenesis.
Collapse
Affiliation(s)
- Jose Luis Olmos-Serrano
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Hyo Jung Kang
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, Connecticut, USA
- Department of Life Science, Chung-Ang University, Seoul, Korea
| | - William A Tyler
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, Massachusetts, USA
| | - John C Silbereis
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, Connecticut, USA
| | - Feng Cheng
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, Connecticut, USA
- Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa, Florida, USA
| | - Ying Zhu
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, Connecticut, USA
| | - Mihovil Pletikos
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, Connecticut, USA
| | - Lucija Jankovic-Rapan
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, Connecticut, USA
| | - Nathan P Cramer
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
| | - Zygmunt Galdzicki
- Department of Anatomy, Physiology, and Genetics, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
| | - Joseph Goodliffe
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Alan Peters
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Claire Sethares
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Ivana Delalle
- Department of Pathology and Laboratory Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Jeffrey A Golden
- Department of Pathology, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Tarik F Haydar
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Nenad Sestan
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, Connecticut, USA
- Departments of Genetic and Psychiatry, Program in Cellular Neuroscience, Neurodegeneration and Repair, Section of Comparative Medicine and Child Study Center, Yale School of Medicine, New Haven, Connecticut, USA
| |
Collapse
|
235
|
A new mechanism of nervous system plasticity: activity-dependent myelination. Nat Rev Neurosci 2016; 16:756-67. [PMID: 26585800 DOI: 10.1038/nrn4023] [Citation(s) in RCA: 441] [Impact Index Per Article: 55.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The synapse is the focus of experimental research and theory on the cellular mechanisms of nervous system plasticity and learning, but recent research is expanding the consideration of plasticity into new mechanisms beyond the synapse, notably including the possibility that conduction velocity could be modifiable through changes in myelin to optimize the timing of information transmission through neural circuits. This concept emerges from a confluence of brain imaging that reveals changes in white matter in the human brain during learning, together with cellular studies showing that the process of myelination can be influenced by action potential firing in axons. This Opinion article summarizes the new research on activity-dependent myelination, explores the possible implications of these studies and outlines the potential for new research.
Collapse
|
236
|
Tomassy GS, Dershowitz LB, Arlotta P. Diversity Matters: A Revised Guide to Myelination. Trends Cell Biol 2016; 26:135-147. [PMID: 26442841 PMCID: PMC4727993 DOI: 10.1016/j.tcb.2015.09.002] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 08/28/2015] [Accepted: 09/01/2015] [Indexed: 11/28/2022]
Abstract
The evolutionary success of the vertebrate nervous system is largely due to a unique structural feature--the myelin sheath, a fatty envelope that surrounds the axons of neurons. By increasing the speed by which electrical signals travel along axons, myelin facilitates neuronal communication between distant regions of the nervous system. We review the cellular and molecular mechanisms that regulate the development of myelin as well as its homeostasis in adulthood. We discuss how finely tuned neuron-oligodendrocyte interactions are central to myelin formation during development and in the adult, and how these interactions can have profound implications for the plasticity of the adult brain. We also speculate how the functional diversity of both neurons and oligodendrocytes may impact on the myelination process in both health and disease.
Collapse
Affiliation(s)
- Giulio Srubek Tomassy
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138, USA.
| | - Lori Bowe Dershowitz
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138, USA
| | - Paola Arlotta
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138, USA.
| |
Collapse
|
237
|
Micu I, Plemel JR, Lachance C, Proft J, Jansen AJ, Cummins K, van Minnen J, Stys PK. The molecular physiology of the axo-myelinic synapse. Exp Neurol 2016; 276:41-50. [DOI: 10.1016/j.expneurol.2015.10.006] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Revised: 10/20/2015] [Accepted: 10/23/2015] [Indexed: 01/18/2023]
|
238
|
Domingues HS, Portugal CC, Socodato R, Relvas JB. Oligodendrocyte, Astrocyte, and Microglia Crosstalk in Myelin Development, Damage, and Repair. Front Cell Dev Biol 2016. [PMID: 27551677 DOI: 10.3389/fcell.2016.00071.ecollection2016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/26/2023] Open
Abstract
Oligodendrocytes are the myelinating glia of the central nervous system. Myelination of axons allows rapid saltatory conduction of nerve impulses and contributes to axonal integrity. Devastating neurological deficits caused by demyelinating diseases, such as multiple sclerosis, illustrate well the importance of the process. In this review, we focus on the positive and negative interactions between oligodendrocytes, astrocytes, and microglia during developmental myelination and remyelination. Even though many lines of evidence support a crucial role for glia crosstalk during these processes, the nature of such interactions is often neglected when designing therapeutics for repair of demyelinated lesions. Understanding the cellular and molecular mechanisms underlying glial cell communication and how they influence oligodendrocyte differentiation and myelination is fundamental to uncover novel therapeutic strategies for myelin repair.
Collapse
Affiliation(s)
- Helena S Domingues
- Glial Cell Biology Group, Instituto de Biologia Molecular e Celular, Universidade do PortoPorto, Portugal; Glial Cell Biology Group, Instituto de Investigação e Inovação em Saúde (I3S), Universidade do PortoPorto, Portugal
| | - Camila C Portugal
- Glial Cell Biology Group, Instituto de Biologia Molecular e Celular, Universidade do PortoPorto, Portugal; Glial Cell Biology Group, Instituto de Investigação e Inovação em Saúde (I3S), Universidade do PortoPorto, Portugal
| | - Renato Socodato
- Glial Cell Biology Group, Instituto de Biologia Molecular e Celular, Universidade do PortoPorto, Portugal; Glial Cell Biology Group, Instituto de Investigação e Inovação em Saúde (I3S), Universidade do PortoPorto, Portugal
| | - João B Relvas
- Glial Cell Biology Group, Instituto de Biologia Molecular e Celular, Universidade do PortoPorto, Portugal; Glial Cell Biology Group, Instituto de Investigação e Inovação em Saúde (I3S), Universidade do PortoPorto, Portugal
| |
Collapse
|
239
|
Interpreting Intervention Induced Neuroplasticity with fMRI: The Case for Multimodal Imaging Strategies. Neural Plast 2015; 2016:2643491. [PMID: 26839711 PMCID: PMC4709757 DOI: 10.1155/2016/2643491] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Accepted: 09/27/2015] [Indexed: 12/03/2022] Open
Abstract
Direct measurement of recovery from brain injury is an important goal in neurorehabilitation, and requires reliable, objective, and interpretable measures of changes in brain function, referred to generally as “neuroplasticity.” One popular imaging modality for measuring neuroplasticity is task-based functional magnetic resonance imaging (t-fMRI). In the field of neurorehabilitation, however, assessing neuroplasticity using t-fMRI presents a significant challenge. This commentary reviews t-fMRI changes commonly reported in patients with cerebral palsy or acquired brain injuries, with a focus on studies of motor rehabilitation, and discusses complexities surrounding their interpretations. Specifically, we discuss the difficulties in interpreting t-fMRI changes in terms of their underlying causes, that is, differentiating whether they reflect genuine reorganisation, neurological restoration, compensation, use of preexisting redundancies, changes in strategy, or maladaptive processes. Furthermore, we discuss the impact of heterogeneous disease states and essential t-fMRI processing steps on the interpretability of activation patterns. To better understand therapy-induced neuroplastic changes, we suggest that researchers utilising t-fMRI consider concurrently acquiring information from an additional modality, to quantify, for example, haemodynamic differences or microstructural changes. We outline a variety of such supplementary measures for investigating brain reorganisation and discuss situations in which they may prove beneficial to the interpretation of t-fMRI data.
Collapse
|
240
|
Park IS, Lee YN, Kwon S, Lee NJ, Rhyu IJ. White matter plasticity in the cerebellum of elite basketball athletes. Anat Cell Biol 2015; 48:262-7. [PMID: 26770877 PMCID: PMC4701700 DOI: 10.5115/acb.2015.48.4.262] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 12/02/2015] [Accepted: 12/03/2015] [Indexed: 11/29/2022] Open
Abstract
Recent neuroimaging studies indicate that learning a novel motor skill induces plastic changes in the brain structures of both gray matter (GM) and white matter (WM) that are associated with a specific practice. We previously reported an increased volume of vermian lobules VI-VII (declive, folium, and tuber) in elite basketball athletes who require coordination for dribbling and shooting a ball, which awakened the central role of the cerebellum in motor coordination. However, the precise factor contributing to the increased volume was not determined. In the present study, we compared the volumes of the GM and WM in the sub-regions of the cerebellar vermis based on manual voxel analysis with the ImageJ program. We found significantly larger WM volumes of vermian lobules VI-VII (declive, folium, and tuber) in elite basketball athletes in response to long-term intensive motor learning. We suggest that the larger WM volumes of this region in elite basketball athletes represent a motor learning-induced plastic change, and that the WM of this region likely plays a critical role in coordination. This finding will contribute to gaining a deeper understanding of motor learning-evoked WM plasticity.
Collapse
Affiliation(s)
- In Sung Park
- Department of Liberal Arts and Teaching Profession, Kyungil University, Gyeongsan, Korea
| | - Ye Na Lee
- Department of Anatomy, Korea University College of Medicine, Seoul, Korea
| | - Soonwook Kwon
- Department of Anatomy, Korea University College of Medicine, Seoul, Korea
| | - Nam Joon Lee
- Department of Diagnostic Radiology, Korea University College of Medicine, Seoul, Korea
| | - Im Joo Rhyu
- Department of Anatomy, Korea University College of Medicine, Seoul, Korea
| |
Collapse
|
241
|
Mouse Hepatitis Virus Infection Remodels Connexin43-Mediated Gap Junction Intercellular Communication In Vitro and In Vivo. J Virol 2015; 90:2586-99. [PMID: 26676788 DOI: 10.1128/jvi.02420-15] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Accepted: 12/12/2015] [Indexed: 01/31/2023] Open
Abstract
UNLABELLED Gap junctions (GJs) form intercellular channels which directly connect the cytoplasm between neighboring cells to facilitate the transfer of ions and small molecules. GJs play a major role in the pathogenesis of infection-associated inflammation. Mutations of gap junction proteins, connexins (Cxs), cause dysmyelination and leukoencephalopathy. In multiple sclerosis (MS) patients and its animal model experimental autoimmune encephalitis (EAE), Cx43 was shown to be modulated in the central nervous system (CNS). The mechanism behind Cx43 alteration and its role in MS remains unexplored. Mouse hepatitis virus (MHV) infection-induced demyelination is one of the best-studied experimental animal models for MS. Our studies demonstrated that MHV infection downregulated Cx43 expression at protein and mRNA levels in vitro in primary astrocytes obtained from neonatal mouse brains. After infection, a significant amount of Cx43 was retained in endoplasmic reticulum/endoplasmic reticulum Golgi intermediate complex (ER/ERGIC) and GJ plaque formation was impaired at the cell surface, as evidenced by a reduction of the Triton X-100 insoluble fraction of Cx43. Altered trafficking and impairment of GJ plaque formation may cause the loss of functional channel formation in MHV-infected primary astrocytes, as demonstrated by a reduced number of dye-coupled cells after a scrape-loading Lucifer yellow dye transfer assay. Upon MHV infection, a significant downregulation of Cx43 was observed in the virus-infected mouse brain. This study demonstrates that astrocytic Cx43 expression and function can be modulated due to virus stress and can be an appropriate model to understand the basis of cellular mechanisms involved in the alteration of gap junction intercellular communication (GJIC) in CNS neuroinflammation. IMPORTANCE We found that MHV infection leads to the downregulation of Cx43 in vivo in the CNS. In addition, results show that MHV infection impairs Cx43 expression in addition to gap junction communication in primary astrocytes. After infection, Cx43 did not traffic normally to the membrane to form gap junction plaques, and that could be the basis of reduced functional gap junction coupling between astrocytes. This is an important first step toward understanding how viruses affect Cx43 expression and trafficking at the cellular level. This may provide a basis for understanding how structural alterations of astrocytic gap junctions can disrupt gap junction communication between other CNS cells in altered CNS environments due to infection and inflammation. More specifically, alteration of Cx43 may be the basis of the destabilization of Cx47 in oligodendrocytes seen in and around inflammatory demyelinating plaques in MS patients.
Collapse
|
242
|
Elsayed M, Magistretti PJ. A New Outlook on Mental Illnesses: Glial Involvement Beyond the Glue. Front Cell Neurosci 2015; 9:468. [PMID: 26733803 PMCID: PMC4679853 DOI: 10.3389/fncel.2015.00468] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 11/16/2015] [Indexed: 12/27/2022] Open
Abstract
Mental illnesses have long been perceived as the exclusive consequence of abnormalities in neuronal functioning. Until recently, the role of glial cells in the pathophysiology of mental diseases has largely been overlooked. However recently, multiple lines of evidence suggest more diverse and significant functions of glia with behavior-altering effects. The newly ascribed roles of astrocytes, oligodendrocytes and microglia have led to their examination in brain pathology and mental illnesses. Indeed, abnormalities in glial function, structure and density have been observed in postmortem brain studies of subjects diagnosed with mental illnesses. In this review, we discuss the newly identified functions of glia and highlight the findings of glial abnormalities in psychiatric disorders. We discuss these preclinical and clinical findings implicating the involvement of glial cells in mental illnesses with the perspective that these cells may represent a new target for treatment.
Collapse
Affiliation(s)
- Maha Elsayed
- Laboratory of Neuroenergetics and Cellular Dynamics, Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne Lausanne, Switzerland
| | - Pierre J Magistretti
- Laboratory of Neuroenergetics and Cellular Dynamics, Brain Mind Institute, Ecole Polytechnique Fédérale de LausanneLausanne, Switzerland; Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and TechnologyThuwal, Saudi Arabia; Department of Psychiatry, Center for Psychiatric Neurosciences, University of LausanneLausanne, Switzerland
| |
Collapse
|
243
|
A model of learning temporal delays, representative of adaptive myelination. BMC Neurosci 2015. [PMCID: PMC4697574 DOI: 10.1186/1471-2202-16-s1-p29] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
|
244
|
Zimmermann H. Extracellular ATP and other nucleotides-ubiquitous triggers of intercellular messenger release. Purinergic Signal 2015; 12:25-57. [PMID: 26545760 DOI: 10.1007/s11302-015-9483-2] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 10/29/2015] [Indexed: 12/21/2022] Open
Abstract
Extracellular nucleotides, and ATP in particular, are cellular signal substances involved in the control of numerous (patho)physiological mechanisms. They provoke nucleotide receptor-mediated mechanisms in select target cells. But nucleotides can considerably expand their range of action. They function as primary messengers in intercellular communication by stimulating the release of other extracellular messenger substances. These in turn activate additional cellular mechanisms through their own receptors. While this applies also to other extracellular messengers, its omnipresence in the vertebrate organism is an outstanding feature of nucleotide signaling. Intercellular messenger substances released by nucleotides include neurotransmitters, hormones, growth factors, a considerable variety of other proteins including enzymes, numerous cytokines, lipid mediators, nitric oxide, and reactive oxygen species. Moreover, nucleotides activate or co-activate growth factor receptors. In the case of hormone release, the initially paracrine or autocrine nucleotide-mediated signal spreads through to the entire organism. The examples highlighted in this commentary suggest that acting as ubiquitous triggers of intercellular messenger release is one of the major functional roles of extracellular nucleotides. While initiation of messenger release by nucleotides has been unraveled in many contexts, it may have been overlooked in others. It can be anticipated that additional nucleotide-driven messenger functions will be uncovered with relevance for both understanding physiology and development of therapy.
Collapse
Affiliation(s)
- Herbert Zimmermann
- Institute of Cell Biology and Neuroscience, Molecular and Cellular Neurobiology, Goethe University, Max-von-Laue-Str. 13, Frankfurt am Main, Germany.
| |
Collapse
|
245
|
Arellano RO, Sánchez-Gómez MV, Alberdi E, Canedo-Antelo M, Chara JC, Palomino A, Pérez-Samartín A, Matute C. Axon-to-Glia Interaction Regulates GABAA Receptor Expression in Oligodendrocytes. Mol Pharmacol 2015; 89:63-74. [PMID: 26538574 DOI: 10.1124/mol.115.100594] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 11/03/2015] [Indexed: 01/02/2023] Open
Abstract
Myelination requires oligodendrocyte-neuron communication, and both neurotransmitters and contact interactions are essential for this process. Oligodendrocytes are endowed with neurotransmitter receptors whose expression levels and properties may change during myelination. However, only scant information is available about the extent and timing of these changes or how they are regulated by oligodendrocyte-neuron interactions. Here, we used electrophysiology to study the expression of ionotropic GABA, glutamate, and ATP receptors in oligodendrocytes derived from the optic nerve and forebrain cultured either alone or in the presence of dorsal root ganglion neurons. We observed that oligodendrocytes from both regions responded to these transmitters at 1 day in culture. After the first day in culture, however, GABA sensitivity diminished drastically to less than 10%, while that of glutamate and ATP remained constant. In contrast, the GABA response amplitude was sustained and remained stable in oligodendrocytes cocultured with dorsal root ganglion neurons. Immunochemistry and pharmacological properties of the responses indicated that they were mediated by distinctive GABAA receptors and that in coculture with neurons, the oligodendrocytes bearing the receptors were those in direct contact with axons. These results reveal that GABAA receptor regulation in oligodendrocytes is driven by axonal cues and that GABA signaling may play a role in myelination and/or during axon-glia recognition.
Collapse
Affiliation(s)
- Rogelio O Arellano
- Achucarro Basque Center for Neuroscience, Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas, and Departamento de Neurociencias, Universidad del País Vasco, Leioa, Spain (R.O.A., M.V.S.-G., E.A., M.C.-A., J.C.C., A.P., A.P.-S., C.M.); and Instituto de Neurobiología, Laboratorio de Neurofisiología Celular, Universidad Nacional Autónoma de México, Juriquilla, Querétaro, México (R.O.A.)
| | - María Victoria Sánchez-Gómez
- Achucarro Basque Center for Neuroscience, Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas, and Departamento de Neurociencias, Universidad del País Vasco, Leioa, Spain (R.O.A., M.V.S.-G., E.A., M.C.-A., J.C.C., A.P., A.P.-S., C.M.); and Instituto de Neurobiología, Laboratorio de Neurofisiología Celular, Universidad Nacional Autónoma de México, Juriquilla, Querétaro, México (R.O.A.)
| | - Elena Alberdi
- Achucarro Basque Center for Neuroscience, Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas, and Departamento de Neurociencias, Universidad del País Vasco, Leioa, Spain (R.O.A., M.V.S.-G., E.A., M.C.-A., J.C.C., A.P., A.P.-S., C.M.); and Instituto de Neurobiología, Laboratorio de Neurofisiología Celular, Universidad Nacional Autónoma de México, Juriquilla, Querétaro, México (R.O.A.)
| | - Manuel Canedo-Antelo
- Achucarro Basque Center for Neuroscience, Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas, and Departamento de Neurociencias, Universidad del País Vasco, Leioa, Spain (R.O.A., M.V.S.-G., E.A., M.C.-A., J.C.C., A.P., A.P.-S., C.M.); and Instituto de Neurobiología, Laboratorio de Neurofisiología Celular, Universidad Nacional Autónoma de México, Juriquilla, Querétaro, México (R.O.A.)
| | - Juan Carlos Chara
- Achucarro Basque Center for Neuroscience, Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas, and Departamento de Neurociencias, Universidad del País Vasco, Leioa, Spain (R.O.A., M.V.S.-G., E.A., M.C.-A., J.C.C., A.P., A.P.-S., C.M.); and Instituto de Neurobiología, Laboratorio de Neurofisiología Celular, Universidad Nacional Autónoma de México, Juriquilla, Querétaro, México (R.O.A.)
| | - Aitor Palomino
- Achucarro Basque Center for Neuroscience, Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas, and Departamento de Neurociencias, Universidad del País Vasco, Leioa, Spain (R.O.A., M.V.S.-G., E.A., M.C.-A., J.C.C., A.P., A.P.-S., C.M.); and Instituto de Neurobiología, Laboratorio de Neurofisiología Celular, Universidad Nacional Autónoma de México, Juriquilla, Querétaro, México (R.O.A.)
| | - Alberto Pérez-Samartín
- Achucarro Basque Center for Neuroscience, Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas, and Departamento de Neurociencias, Universidad del País Vasco, Leioa, Spain (R.O.A., M.V.S.-G., E.A., M.C.-A., J.C.C., A.P., A.P.-S., C.M.); and Instituto de Neurobiología, Laboratorio de Neurofisiología Celular, Universidad Nacional Autónoma de México, Juriquilla, Querétaro, México (R.O.A.)
| | - Carlos Matute
- Achucarro Basque Center for Neuroscience, Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas, and Departamento de Neurociencias, Universidad del País Vasco, Leioa, Spain (R.O.A., M.V.S.-G., E.A., M.C.-A., J.C.C., A.P., A.P.-S., C.M.); and Instituto de Neurobiología, Laboratorio de Neurofisiología Celular, Universidad Nacional Autónoma de México, Juriquilla, Querétaro, México (R.O.A.)
| |
Collapse
|
246
|
Olfactory bulb and olfactory sulcus depths are associated with disease duration and attack frequency in multiple sclerosis patients. J Neurol Sci 2015; 358:304-7. [DOI: 10.1016/j.jns.2015.09.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Revised: 08/14/2015] [Accepted: 09/07/2015] [Indexed: 11/20/2022]
|
247
|
Ergul A, Valenzuela JP, Fouda AY, Fagan SC. Cellular connections, microenvironment and brain angiogenesis in diabetes: Lost communication signals in the post-stroke period. Brain Res 2015; 1623:81-96. [PMID: 25749094 PMCID: PMC4743654 DOI: 10.1016/j.brainres.2015.02.045] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 02/18/2015] [Accepted: 02/23/2015] [Indexed: 12/16/2022]
Abstract
Diabetes not only increases the risk but also worsens the motor and cognitive recovery after stroke, which is the leading cause of disability worldwide. Repair after stroke requires coordinated communication among various cell types in the central nervous system as well as circulating cells. Vascular restoration is critical for the enhancement of neurogenesis and neuroplasticity. Given that vascular disease is a major component of all complications associated with diabetes including stroke, this review will focus on cellular communications that are important for vascular restoration in the context of diabetes. This article is part of a Special Issue entitled SI: Cell Interactions In Stroke.
Collapse
Affiliation(s)
- Adviye Ergul
- Charlie Norwood Veterans Affairs Medical Center, Augusta, GA 30904, USA; Department of Physiology, Medical College of Georgia, Georgia Regents University, 1120 15th Street, CA 2094, Augusta, GA 30912, USA; Program in Clinical and Experimental Therapeutics, College of Pharmacy, University of Georgia, Augusta, GA 30912, USA.
| | - John Paul Valenzuela
- Department of Physiology, Medical College of Georgia, Georgia Regents University, 1120 15th Street, CA 2094, Augusta, GA 30912, USA
| | - Abdelrahman Y Fouda
- Charlie Norwood Veterans Affairs Medical Center, Augusta, GA 30904, USA; Program in Clinical and Experimental Therapeutics, College of Pharmacy, University of Georgia, Augusta, GA 30912, USA
| | - Susan C Fagan
- Charlie Norwood Veterans Affairs Medical Center, Augusta, GA 30904, USA; Department of Neurology, Medical College of Georgia, Georgia Regents University, Augusta, GA 30912, USA; Program in Clinical and Experimental Therapeutics, College of Pharmacy, University of Georgia, Augusta, GA 30912, USA
| |
Collapse
|
248
|
Rosenzweig S, Carmichael ST. The axon-glia unit in white matter stroke: mechanisms of damage and recovery. Brain Res 2015; 1623:123-34. [PMID: 25704204 PMCID: PMC4545468 DOI: 10.1016/j.brainres.2015.02.019] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2015] [Accepted: 02/10/2015] [Indexed: 01/07/2023]
Abstract
Approximately one quarter of all strokes in humans occur in white matter, and the progressive nature of white matter lesions often results in severe physical and mental disability. Unlike cortical grey matter stroke, the pathology of white matter stroke revolves around disrupted connectivity and injured axons and glial cells, rather than neuronal cell bodies. Consequently, the mechanisms behind ischemic damage to white matter elements, the regenerative responses of glial cells and their signaling pathways, all differ significantly from those in grey matter. Development of effective therapies for white matter stroke would require an enhanced understanding of the complex cellular and molecular interactions within the white matter, leading to the identification of new therapeutic targets. This review will address the unique properties of the axon-glia unit during white matter stroke, describe the challenging process of promoting effective white matter repair, and discuss recently-identified signaling pathways which may hold potential targets for repair in this disease. This article is part of a Special Issue entitled SI: Cell Interactions In Stroke.
Collapse
Affiliation(s)
- Shira Rosenzweig
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA.
| | - S Thomas Carmichael
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA.
| |
Collapse
|
249
|
Carper RA, Solders S, Treiber JM, Fishman I, Müller RA. Corticospinal tract anatomy and functional connectivity of primary motor cortex in autism. J Am Acad Child Adolesc Psychiatry 2015; 54:859-67. [PMID: 26407496 PMCID: PMC4697829 DOI: 10.1016/j.jaac.2015.07.007] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 05/28/2015] [Accepted: 07/29/2015] [Indexed: 12/14/2022]
Abstract
OBJECTIVE Growing evidence indicates that autism spectrum disorder (ASD) stems from abnormal structural and functional connectivity of neural networks. Although diagnostic symptoms are sociocommunicative, motor-related functions (beyond repetitive mannerisms) are also impaired. However, evidence on connectivity at the level of basic motor execution is limited, which we address here. METHOD We compared right-handed children and adolescents (aged 7-18 years) with ASD (n = 44) to matched typically developing participants (TD, n = 36) using magnetic resonance imaging (MRI). Diffusion-weighted imaging and probabilistic tractography measured microstructure of the corticospinal tract (CST). Intrinsic functional connectivity MRI examined whole-brain voxelwise correlations, both with identical precentral gyrus (PCG) seeds. RESULTS In the group with ASD, radial and mean diffusivity were increased bilaterally in the CST, particularly in superior segments, and a leftward asymmetry of CST volume detected in the TD group was reversed. Functionally, overconnectivity was found for both left and right PCG with prefrontal, parietal, medial occipital, and cingulate cortices. The group with ASD also showed significantly reduced asymmetry of functional connectivity for both left and right PCG seeds. Finally, in the group with ASD, significant correlations were found for functional overconnectivity of the right PCG seed with anisotropy and mean diffusivity in the right CST. CONCLUSION The findings, implicating both functional and anatomical connectivity of the primary motor cortex, suggest that network anomalies in ASD go well beyond sociocommunicative domains, affecting basic motor execution. They also suggest that even in right-handed adolescents with ASD, typical left hemisphere dominance is reduced, both anatomically and functionally, with an unusual degree of right hemisphere motor participation.
Collapse
Affiliation(s)
- Ruth A Carper
- Brain Development Imaging Laboratory at San Diego State University, CA.
| | - Seraphina Solders
- Brain Development Imaging Laboratory at San Diego State University, CA
| | | | - Inna Fishman
- Brain Development Imaging Laboratory at San Diego State University, CA
| | - Ralph-Axel Müller
- Brain Development Imaging Laboratory at San Diego State University, CA
| |
Collapse
|
250
|
Pacey LKK, Guan S, Tharmalingam S, Thomsen C, Hampson DR. Persistent astrocyte activation in the fragile X mouse cerebellum. Brain Behav 2015; 5:e00400. [PMID: 26516618 PMCID: PMC4614053 DOI: 10.1002/brb3.400] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 07/31/2015] [Accepted: 08/21/2015] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Fragile X Syndrome, the most common single gene cause of autism, results from loss of the RNA-binding protein FMRP. Although FMRP is highly expressed in neurons, it has also recently been identified in glia. It has been postulated that in the absence of FMRP, abnormal function of non-neuronal cells may contribute to the pathogenesis of the disorder. We previously demonstrated reduced numbers of oligodendrocyte precursor cells and delayed myelination in the cerebellum of fragile X (Fmr1) knockout mice. METHODS We used quantitative western blotting and immunocytochemistry to examine the status of astrocytes and microglia in the cerebellum of Fmr1 mice during development and in adulthood. RESULTS We report increased expression of the astrocyte marker GFAP in the cerebellum of Fmr1 mice starting in the second postnatal week and persisting in to adulthood. At 2 weeks postnatal, expression of Tumor Necrosis Factor Receptor 2 (TNFR2) and Leukemia Inhibitory Factor (LIF) were elevated in the Fmr1 KO cerebellum. In adults, expression of TNFR2 and the glial marker S100β were also elevated in Fmr1 knockouts, but LIF expression was not different from wild-type mice. We found no evidence of microglial activation or neuroinflammation at any age examined. CONCLUSIONS These findings demonstrate an atypical pattern of astrogliosis in the absence of microglial activation in Fmr1 knockout mouse cerebellum. Enhanced TNFR2 and LIF expression in young mice suggests that changes in the expression of astrocytic proteins may be an attempt to compensate for delayed myelination in the developing cerebellum of Fmr1 mice.
Collapse
Affiliation(s)
- Laura K K Pacey
- Department of Pharmaceutical Sciences Leslie Dan Faculty of Pharmacy University of Toronto 144 College Street Toronto Ontario Canada M5S 3M2
| | - Sihui Guan
- Department of Pharmaceutical Sciences Leslie Dan Faculty of Pharmacy University of Toronto 144 College Street Toronto Ontario Canada M5S 3M2
| | - Sujeenthar Tharmalingam
- Department of Pharmaceutical Sciences Leslie Dan Faculty of Pharmacy University of Toronto 144 College Street Toronto Ontario Canada M5S 3M2
| | - Christian Thomsen
- Department of Neuroinflammation Lundbeck Research USA 215 College Road Paramus New Jersey 07652
| | - David R Hampson
- Department of Pharmaceutical Sciences Leslie Dan Faculty of Pharmacy University of Toronto 144 College Street Toronto Ontario Canada M5S 3M2 ; Department of Pharmacology Faculty of Medicine University of Toronto 144 College Street Toronto Ontario Canada M5S 3M2
| |
Collapse
|