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Cognitive impairments correlate with increased central nervous system immune activation after allogeneic haematopoietic stem cell transplantation. Leukemia 2023; 37:888-900. [PMID: 36792657 PMCID: PMC10079537 DOI: 10.1038/s41375-023-01840-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/30/2023] [Accepted: 02/02/2023] [Indexed: 02/17/2023]
Abstract
Murine studies indicate that, after allogeneic haematopoietic stem cell transplantation (aHSCT), donor-derived macrophages replace damaged microglia and alloreactive T-cells invade the central nervous system (CNS). The clinical relevance of this is unknown. We assessed CNS immune surveillance and metabolic activity involved in neuronal survival, in relation to fatigue and cognitive dysfunction in 25 long-term survivors after aHSCT. Patients with cognitive dysfunction exhibited increased proportions of activated T-cells and CD16 + NK-cells in the cerebrospinal fluid (CSF). Immune cell activation was paralleled with reduced levels of anti-inflammatory factors involved in T-cell suppression (transforming growth factor-β, programmed death ligand-1), NK-cell regulation (poliovirus receptor, nectin-2), and macrophage and microglia activation (CD200, chemokine [C-X3-C motif] ligand-1). Additionally, the CSF mRNA expression pattern was associated with neuroinflammation and oxidative stress. Furthermore, proteomic, and transcriptomic studies demonstrated decreased levels of neuroprotective factors, and an upregulation of apoptosis pathway genes. The kynurenine pathway of tryptophan metabolism was activated in the CNS of all aHSCT patients, resulting in accumulation of neurotoxic and pro-inflammatory metabolites. Cognitive decline and fatigue are overlooked but frequent complications of aHSCT. This study links post-transplant CNS inflammation and neurotoxicity to our previously reported hypoactivation in the prefrontal cortex during cognitive testing, suggesting novel treatment targets.
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Cirac A, Tsaktanis T, Beyer T, Linnerbauer M, Andlauer T, Grummel V, Nirschl L, Loesslein L, Quintana FJ, Hemmer B, Rothhammer V. The Aryl Hydrocarbon Receptor-Dependent TGF-α/VEGF-B Ratio Correlates With Disease Subtype and Prognosis in Multiple Sclerosis. NEUROLOGY-NEUROIMMUNOLOGY & NEUROINFLAMMATION 2021; 8:8/5/e1043. [PMID: 34301821 PMCID: PMC8312279 DOI: 10.1212/nxi.0000000000001043] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Accepted: 05/28/2021] [Indexed: 11/15/2022]
Abstract
OBJECTIVE To evaluate the aryl hydrocarbon receptor (AHR)-dependent transforming growth factor alpha (TGF-α)/vascular endothelial growth factor B (VEGF-B) ratio, which regulates the effects of metabolic, dietary, and microbial factors on acute and chronic CNS inflammation, as a potential marker in multiple sclerosis (MS). METHODS TGF-α, VEGF-B, and AHR agonistic activity were determined in serum of 252 patients with relapsing-remitting (RR) MS, primary and secondary progressive MS, as well as during active disease (clinically isolated syndrome [CIS] and RRMS relapse). RESULTS The TGF-α/VEGF-B ratio and AHR agonistic activity were decreased in all MS subgroups with a stable disease course as compared to controls. During active CNS inflammation in CIS and RRMS relapse, the TGF-α/VEGF-B ratio and AHR agonistic activity were increased. Conversely, in patients with minimal clinical impairment despite long-standing disease, the TGF-α/VEGF-B ratio and AHR agonistic activity were unaltered. Finally, the TGF-α/VEGF-B ratio and AHR agonistic activity correlated with neurologic impairment and time to conversion from CIS to MS. CONCLUSIONS The AHR-dependent TGF-α/VEGF-B ratio is altered in a subtype, severity, and disease activity-specific manner and correlates with time to conversion from CIS to MS. It may thus represent a novel marker and serve as additive guideline for immunomodulatory strategies in MS. CLASSIFICATION OF EVIDENCE This study provides Class III evidence that serum levels of AHR, TGF-α, and VEGF-B distinguish subtypes of MS and predict the severity and disease activity of MS.
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Affiliation(s)
- Ana Cirac
- From the Department of Neurology (A.C., T.T., T.B., M.L., T.A., V.G., L.N., B.H., V.R.), Klinikum Rechts der Isar, Technical University of Munich Department of Neurology (T.T., M.L., L.L., V.R.), University Hospital Erlangen, Friedrich Alexander University Erlangen-Nuernberg, Germany; Ann Romney Center for Neurologic Diseases (F.J.Q.), Brigham and Women's Hospital, Harvard Medical School, Boston; Broad Institute of MIT and Harvard (F.J.Q.), Cambridge, MA; and Munich Cluster for Systems Neurology (SyNergy) (B.H.), Germany
| | - Thanos Tsaktanis
- From the Department of Neurology (A.C., T.T., T.B., M.L., T.A., V.G., L.N., B.H., V.R.), Klinikum Rechts der Isar, Technical University of Munich Department of Neurology (T.T., M.L., L.L., V.R.), University Hospital Erlangen, Friedrich Alexander University Erlangen-Nuernberg, Germany; Ann Romney Center for Neurologic Diseases (F.J.Q.), Brigham and Women's Hospital, Harvard Medical School, Boston; Broad Institute of MIT and Harvard (F.J.Q.), Cambridge, MA; and Munich Cluster for Systems Neurology (SyNergy) (B.H.), Germany
| | - Tobias Beyer
- From the Department of Neurology (A.C., T.T., T.B., M.L., T.A., V.G., L.N., B.H., V.R.), Klinikum Rechts der Isar, Technical University of Munich Department of Neurology (T.T., M.L., L.L., V.R.), University Hospital Erlangen, Friedrich Alexander University Erlangen-Nuernberg, Germany; Ann Romney Center for Neurologic Diseases (F.J.Q.), Brigham and Women's Hospital, Harvard Medical School, Boston; Broad Institute of MIT and Harvard (F.J.Q.), Cambridge, MA; and Munich Cluster for Systems Neurology (SyNergy) (B.H.), Germany
| | - Mathias Linnerbauer
- From the Department of Neurology (A.C., T.T., T.B., M.L., T.A., V.G., L.N., B.H., V.R.), Klinikum Rechts der Isar, Technical University of Munich Department of Neurology (T.T., M.L., L.L., V.R.), University Hospital Erlangen, Friedrich Alexander University Erlangen-Nuernberg, Germany; Ann Romney Center for Neurologic Diseases (F.J.Q.), Brigham and Women's Hospital, Harvard Medical School, Boston; Broad Institute of MIT and Harvard (F.J.Q.), Cambridge, MA; and Munich Cluster for Systems Neurology (SyNergy) (B.H.), Germany
| | - Till Andlauer
- From the Department of Neurology (A.C., T.T., T.B., M.L., T.A., V.G., L.N., B.H., V.R.), Klinikum Rechts der Isar, Technical University of Munich Department of Neurology (T.T., M.L., L.L., V.R.), University Hospital Erlangen, Friedrich Alexander University Erlangen-Nuernberg, Germany; Ann Romney Center for Neurologic Diseases (F.J.Q.), Brigham and Women's Hospital, Harvard Medical School, Boston; Broad Institute of MIT and Harvard (F.J.Q.), Cambridge, MA; and Munich Cluster for Systems Neurology (SyNergy) (B.H.), Germany
| | - Verena Grummel
- From the Department of Neurology (A.C., T.T., T.B., M.L., T.A., V.G., L.N., B.H., V.R.), Klinikum Rechts der Isar, Technical University of Munich Department of Neurology (T.T., M.L., L.L., V.R.), University Hospital Erlangen, Friedrich Alexander University Erlangen-Nuernberg, Germany; Ann Romney Center for Neurologic Diseases (F.J.Q.), Brigham and Women's Hospital, Harvard Medical School, Boston; Broad Institute of MIT and Harvard (F.J.Q.), Cambridge, MA; and Munich Cluster for Systems Neurology (SyNergy) (B.H.), Germany
| | - Lucy Nirschl
- From the Department of Neurology (A.C., T.T., T.B., M.L., T.A., V.G., L.N., B.H., V.R.), Klinikum Rechts der Isar, Technical University of Munich Department of Neurology (T.T., M.L., L.L., V.R.), University Hospital Erlangen, Friedrich Alexander University Erlangen-Nuernberg, Germany; Ann Romney Center for Neurologic Diseases (F.J.Q.), Brigham and Women's Hospital, Harvard Medical School, Boston; Broad Institute of MIT and Harvard (F.J.Q.), Cambridge, MA; and Munich Cluster for Systems Neurology (SyNergy) (B.H.), Germany
| | - Lena Loesslein
- From the Department of Neurology (A.C., T.T., T.B., M.L., T.A., V.G., L.N., B.H., V.R.), Klinikum Rechts der Isar, Technical University of Munich Department of Neurology (T.T., M.L., L.L., V.R.), University Hospital Erlangen, Friedrich Alexander University Erlangen-Nuernberg, Germany; Ann Romney Center for Neurologic Diseases (F.J.Q.), Brigham and Women's Hospital, Harvard Medical School, Boston; Broad Institute of MIT and Harvard (F.J.Q.), Cambridge, MA; and Munich Cluster for Systems Neurology (SyNergy) (B.H.), Germany
| | - Francisco J Quintana
- From the Department of Neurology (A.C., T.T., T.B., M.L., T.A., V.G., L.N., B.H., V.R.), Klinikum Rechts der Isar, Technical University of Munich Department of Neurology (T.T., M.L., L.L., V.R.), University Hospital Erlangen, Friedrich Alexander University Erlangen-Nuernberg, Germany; Ann Romney Center for Neurologic Diseases (F.J.Q.), Brigham and Women's Hospital, Harvard Medical School, Boston; Broad Institute of MIT and Harvard (F.J.Q.), Cambridge, MA; and Munich Cluster for Systems Neurology (SyNergy) (B.H.), Germany
| | - Bernhard Hemmer
- From the Department of Neurology (A.C., T.T., T.B., M.L., T.A., V.G., L.N., B.H., V.R.), Klinikum Rechts der Isar, Technical University of Munich Department of Neurology (T.T., M.L., L.L., V.R.), University Hospital Erlangen, Friedrich Alexander University Erlangen-Nuernberg, Germany; Ann Romney Center for Neurologic Diseases (F.J.Q.), Brigham and Women's Hospital, Harvard Medical School, Boston; Broad Institute of MIT and Harvard (F.J.Q.), Cambridge, MA; and Munich Cluster for Systems Neurology (SyNergy) (B.H.), Germany
| | - Veit Rothhammer
- From the Department of Neurology (A.C., T.T., T.B., M.L., T.A., V.G., L.N., B.H., V.R.), Klinikum Rechts der Isar, Technical University of Munich Department of Neurology (T.T., M.L., L.L., V.R.), University Hospital Erlangen, Friedrich Alexander University Erlangen-Nuernberg, Germany; Ann Romney Center for Neurologic Diseases (F.J.Q.), Brigham and Women's Hospital, Harvard Medical School, Boston; Broad Institute of MIT and Harvard (F.J.Q.), Cambridge, MA; and Munich Cluster for Systems Neurology (SyNergy) (B.H.), Germany.
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Bressan C, Saghatelyan A. Intrinsic Mechanisms Regulating Neuronal Migration in the Postnatal Brain. Front Cell Neurosci 2021; 14:620379. [PMID: 33519385 PMCID: PMC7838331 DOI: 10.3389/fncel.2020.620379] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 12/08/2020] [Indexed: 01/19/2023] Open
Abstract
Neuronal migration is a fundamental brain development process that allows cells to move from their birthplaces to their sites of integration. Although neuronal migration largely ceases during embryonic and early postnatal development, neuroblasts continue to be produced and to migrate to a few regions of the adult brain such as the dentate gyrus and the subventricular zone (SVZ). In the SVZ, a large number of neuroblasts migrate into the olfactory bulb (OB) along the rostral migratory stream (RMS). Neuroblasts migrate in chains in a tightly organized micro-environment composed of astrocytes that ensheath the chains of neuroblasts and regulate their migration; the blood vessels that are used by neuroblasts as a physical scaffold and a source of molecular factors; and axons that modulate neuronal migration. In addition to diverse sets of extrinsic micro-environmental cues, long-distance neuronal migration involves a number of intrinsic mechanisms, including membrane and cytoskeleton remodeling, Ca2+ signaling, mitochondria dynamics, energy consumption, and autophagy. All these mechanisms are required to cope with the different micro-environment signals and maintain cellular homeostasis in order to sustain the proper dynamics of migrating neuroblasts and their faithful arrival in the target regions. Neuroblasts in the postnatal brain not only migrate into the OB but may also deviate from their normal path to migrate to a site of injury induced by a stroke or by certain neurodegenerative disorders. In this review, we will focus on the intrinsic mechanisms that regulate long-distance neuroblast migration in the adult brain and on how these pathways may be modulated to control the recruitment of neuroblasts to damaged/diseased brain areas.
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Affiliation(s)
- Cedric Bressan
- CERVO Brain Research Center, Quebec City, QC, Canada.,Department of Psychiatry and Neuroscience, Université Laval, Quebec City, QC, Canada
| | - Armen Saghatelyan
- CERVO Brain Research Center, Quebec City, QC, Canada.,Department of Psychiatry and Neuroscience, Université Laval, Quebec City, QC, Canada
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Scalabrino G. Epidermal Growth Factor in the CNS: A Beguiling Journey from Integrated Cell Biology to Multiple Sclerosis. An Extensive Translational Overview. Cell Mol Neurobiol 2020; 42:891-916. [PMID: 33151415 PMCID: PMC8942922 DOI: 10.1007/s10571-020-00989-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 10/23/2020] [Indexed: 12/16/2022]
Abstract
This article reviews the wealth of papers dealing with the different effects of epidermal growth factor (EGF) on oligodendrocytes, astrocytes, neurons, and neural stem cells (NSCs). EGF induces the in vitro and in vivo proliferation of NSCs, their migration, and their differentiation towards the neuroglial cell line. It interacts with extracellular matrix components. NSCs are distributed in different CNS areas, serve as a reservoir of multipotent cells, and may be increased during CNS demyelinating diseases. EGF has pleiotropic differentiative and proliferative effects on the main CNS cell types, particularly oligodendrocytes and their precursors, and astrocytes. EGF mediates the in vivo myelinotrophic effect of cobalamin on the CNS, and modulates the synthesis and levels of CNS normal prions (PrPCs), both of which are indispensable for myelinogenesis and myelin maintenance. EGF levels are significantly lower in the cerebrospinal fluid and spinal cord of patients with multiple sclerosis (MS), which probably explains remyelination failure, also because of the EGF marginal role in immunology. When repeatedly administered, EGF protects mouse spinal cord from demyelination in various experimental models of autoimmune encephalomyelitis. It would be worth further investigating the role of EGF in the pathogenesis of MS because of its multifarious effects.
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Affiliation(s)
- Giuseppe Scalabrino
- Department of Biomedical Sciences, University of Milan, Via Mangiagalli 31, 20133, Milan, Italy.
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Lin B, Wang Y, Zhang P, Yuan Y, Zhang Y, Chen G. Gut microbiota regulates neuropathic pain: potential mechanisms and therapeutic strategy. J Headache Pain 2020; 21:103. [PMID: 32807072 PMCID: PMC7433133 DOI: 10.1186/s10194-020-01170-x] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 08/10/2020] [Indexed: 02/08/2023] Open
Abstract
Neuropathic pain (NP) is a sustained and nonreversible condition characterized by long-term devastating physical and psychological damage. Therefore, it is urgent to identify an effective treatment for NP. Unfortunately, the precise pathogenesis of NP has not been elucidated. Currently, the microbiota-gut-brain axis has drawn increasing attention, and the emerging role of gut microbiota is investigated in numerous diseases including NP. Gut microbiota is considered as a pivotal regulator in immune, neural, endocrine, and metabolic signaling pathways, which participates in forming a complex network to affect the development of NP directly or indirectly. In this review, we conclude the current understanding of preclinical and clinical findings regarding the role of gut microbiota in NP and provide a novel therapeutic method for pain relief by medication and dietary interventions.
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Affiliation(s)
- Binbin Lin
- Department of Anesthesiology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, 3 Qingchun East Road, Zhejiang, 310016, Hangzhou, China
| | - Yuting Wang
- Department of Anesthesiology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, 3 Qingchun East Road, Zhejiang, 310016, Hangzhou, China
| | - Piao Zhang
- Department of Anesthesiology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, 3 Qingchun East Road, Zhejiang, 310016, Hangzhou, China
| | - Yanyan Yuan
- Department of Anesthesiology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, 3 Qingchun East Road, Zhejiang, 310016, Hangzhou, China
| | - Ying Zhang
- Department of Anesthesiology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, 3 Qingchun East Road, Zhejiang, 310016, Hangzhou, China
| | - Gang Chen
- Department of Anesthesiology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, 3 Qingchun East Road, Zhejiang, 310016, Hangzhou, China.
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6
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Crossland H, Piasecki J, McCormick D, Phillips BE, Wilkinson DJ, Smith K, McPhee JS, Piasecki M, Atherton PJ. Targeted genotype analyses of GWAS-derived lean body mass and handgrip strength-associated single-nucleotide polymorphisms in elite master athletes. Am J Physiol Regul Integr Comp Physiol 2020; 319:R184-R194. [PMID: 32579386 PMCID: PMC7473897 DOI: 10.1152/ajpregu.00110.2020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 06/18/2020] [Accepted: 06/18/2020] [Indexed: 01/24/2023]
Abstract
Recent large genome-wide association studies (GWAS) have independently identified a set of genetic loci associated with lean body mass (LBM) and handgrip strength (HGS). Evaluation of these candidate single-nucleotide polymorphisms (SNPs) may be useful to investigate genetic traits of populations at higher or lower risk of muscle dysfunction. As such, we investigated associations between six SNPs linked to LBM or HGS in a population of elite master athletes (MA) and age-matched controls as a representative population of older individuals with variable maintenance of muscle mass and function. Genomic DNA was isolated from buffy coat samples of 96 individuals [consisting of 48 MA (71 ± 6 yr, age-graded performance 83 ± 9%) and 48 older controls (75 ± 6 yr)]. SNP validation and sample genotyping were conducted using the tetra-primer amplification refractory mutation system (ARMS). For the three SNPs analyzed that were previously associated with LBM (FTO, IRS1, and ADAMTSL3), multinomial logistic regression revealed a significant association of the ADAMTSL3 genotype with %LBM (P < 0.01). For the three HGS-linked SNPs, neither GBF1 nor GLIS1 showed any association with HGS, but for TGFA, multinomial logistic regression revealed a significant association of genotype with HGS (P < 0.05). For ADAMTSL3, there was an enrichment of the effect allele in the MA (P < 0.05, Fisher's exact test). Collectively, of the six SNPs analyzed, ADAMTSL3 and TGFA showed significant associations with LBM and HGS, respectively. The functional relevance of the ADAMTSL3 SNP in body composition and of TGFA in strength may highlight a genetic component of the elite MA phenotype.
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Affiliation(s)
- Hannah Crossland
- Medical Research Council Versus Arthritis Centre for Musculoskeletal Ageing Research and National Institute of Health Research Nottingham Biomedical Research Centre, University of Nottingham, Royal Derby Hospital Centre, Nottingham, United Kingdom
| | - Jessica Piasecki
- Musculoskeletal Physiology Research Group, Sport, Health and Performance Enhancement Research Centre, School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom
| | - Daniel McCormick
- Medical Research Council Versus Arthritis Centre for Musculoskeletal Ageing Research and National Institute of Health Research Nottingham Biomedical Research Centre, University of Nottingham, Royal Derby Hospital Centre, Nottingham, United Kingdom
| | - Bethan E Phillips
- Medical Research Council Versus Arthritis Centre for Musculoskeletal Ageing Research and National Institute of Health Research Nottingham Biomedical Research Centre, University of Nottingham, Royal Derby Hospital Centre, Nottingham, United Kingdom
| | - Daniel J Wilkinson
- Medical Research Council Versus Arthritis Centre for Musculoskeletal Ageing Research and National Institute of Health Research Nottingham Biomedical Research Centre, University of Nottingham, Royal Derby Hospital Centre, Nottingham, United Kingdom
| | - Kenneth Smith
- Medical Research Council Versus Arthritis Centre for Musculoskeletal Ageing Research and National Institute of Health Research Nottingham Biomedical Research Centre, University of Nottingham, Royal Derby Hospital Centre, Nottingham, United Kingdom
| | - Jamie S McPhee
- Department of Sport and Exercise Sciences, Faculty of Science and Engineering, Manchester Metropolitan University, Manchester, United Kingdom
| | - Mathew Piasecki
- Medical Research Council Versus Arthritis Centre for Musculoskeletal Ageing Research and National Institute of Health Research Nottingham Biomedical Research Centre, University of Nottingham, Royal Derby Hospital Centre, Nottingham, United Kingdom
| | - Philip J Atherton
- Medical Research Council Versus Arthritis Centre for Musculoskeletal Ageing Research and National Institute of Health Research Nottingham Biomedical Research Centre, University of Nottingham, Royal Derby Hospital Centre, Nottingham, United Kingdom
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7
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Current Medical Therapy and Future Trends in the Management of Glaucoma Treatment. J Ophthalmol 2020; 2020:6138132. [PMID: 32774906 PMCID: PMC7391108 DOI: 10.1155/2020/6138132] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 06/29/2020] [Indexed: 01/02/2023] Open
Abstract
Glaucoma is a neurodegenerative disease characterized by progressive loss of retinal ganglion cells and their axons. Lowering of intraocular pressure (IOP) is currently the only proven treatment strategy for glaucoma. However, some patients show progressive loss of visual field and quality of life despite controlled IOP which indicates that other factors are implicated in glaucoma. Therefore, approaches that could prevent or decrease the rate of progression and do not rely on IOP lowering have gained much attention. Effective neuroprotection has been reported in animal models of glaucoma, but till now, no neuroprotective agents have been clinically approved. The present update provides an overview of currently available IOP-lowering medications. Moreover, potential new treatment targets for IOP-lowering and neuroprotective therapy are discussed. Finally, future trends in glaucoma therapy are addressed, including sustained drug delivery systems and progress toward personalized medicine.
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Rothhammer V, Borucki DM, Tjon EC, Takenaka MC, Chao CC, Ardura-Fabregat A, de Lima KA, Gutiérrez-Vázquez C, Hewson P, Staszewski O, Blain M, Healy L, Neziraj T, Borio M, Wheeler M, Dragin LL, Laplaud DA, Antel J, Alvarez JI, Prinz M, Quintana FJ. Microglial control of astrocytes in response to microbial metabolites. Nature 2018; 557:724-728. [PMID: 29769726 DOI: 10.1038/s41586-018-0119-x] [Citation(s) in RCA: 634] [Impact Index Per Article: 105.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 04/11/2018] [Indexed: 12/14/2022]
Abstract
Microglia and astrocytes modulate inflammation and neurodegeneration in the central nervous system (CNS)1-3. Microglia modulate pro-inflammatory and neurotoxic activities in astrocytes, but the mechanisms involved are not completely understood4,5. Here we report that TGFα and VEGF-B produced by microglia regulate the pathogenic activities of astrocytes in the experimental autoimmune encephalomyelitis (EAE) mouse model of multiple sclerosis. Microglia-derived TGFα acts via the ErbB1 receptor in astrocytes to limit their pathogenic activities and EAE development. Conversely, microglial VEGF-B triggers FLT-1 signalling in astrocytes and worsens EAE. VEGF-B and TGFα also participate in the microglial control of human astrocytes. Furthermore, expression of TGFα and VEGF-B in CD14+ cells correlates with the multiple sclerosis lesion stage. Finally, metabolites of dietary tryptophan produced by the commensal flora control microglial activation and TGFα and VEGF-B production, modulating the transcriptional program of astrocytes and CNS inflammation through a mechanism mediated by the aryl hydrocarbon receptor. In summary, we identified positive and negative regulators that mediate the microglial control of astrocytes. Moreover, these findings define a pathway through which microbial metabolites limit pathogenic activities of microglia and astrocytes, and suppress CNS inflammation. This pathway may guide new therapies for multiple sclerosis and other neurological disorders.
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Affiliation(s)
- Veit Rothhammer
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Davis M Borucki
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Emily C Tjon
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Maisa C Takenaka
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Chun-Cheih Chao
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | | | - Kalil Alves de Lima
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Cristina Gutiérrez-Vázquez
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Patrick Hewson
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Ori Staszewski
- Institute of Neuropathology, Medical Faculty, University of Freiburg, Freiburg, Germany
| | - Manon Blain
- Neuroimmunology Unit, Montreal Neurological Institute, Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada
| | - Luke Healy
- Neuroimmunology Unit, Montreal Neurological Institute, Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada
| | - Tradite Neziraj
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Matilde Borio
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Michael Wheeler
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Loic Lionel Dragin
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | | | - Jack Antel
- Neuroimmunology Unit, Montreal Neurological Institute, Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada
| | - Jorge Ivan Alvarez
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Marco Prinz
- Institute of Neuropathology, Medical Faculty, University of Freiburg, Freiburg, Germany.,BIOSS Centre for Biological Signaling Studies, University of Freiburg, Freiburg, Germany
| | - Francisco J Quintana
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA. .,Broad Institute of MIT and Harvard, Cambridge, MA, USA.
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9
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Willems SM, Wright DJ, Day FR, Trajanoska K, Joshi PK, Morris JA, Matteini AM, Garton FC, Grarup N, Oskolkov N, Thalamuthu A, Mangino M, Liu J, Demirkan A, Lek M, Xu L, Wang G, Oldmeadow C, Gaulton KJ, Lotta LA, Miyamoto-Mikami E, Rivas MA, White T, Loh PR, Aadahl M, Amin N, Attia JR, Austin K, Benyamin B, Brage S, Cheng YC, Cięszczyk P, Derave W, Eriksson KF, Eynon N, Linneberg A, Lucia A, Massidda M, Mitchell BD, Miyachi M, Murakami H, Padmanabhan S, Pandey A, Papadimitriou I, Rajpal DK, Sale C, Schnurr TM, Sessa F, Shrine N, Tobin MD, Varley I, Wain LV, Wray NR, Lindgren CM, MacArthur DG, Waterworth DM, McCarthy MI, Pedersen O, Khaw KT, Kiel DP, Pitsiladis Y, Fuku N, Franks PW, North KN, van Duijn CM, Mather KA, Hansen T, Hansson O, Spector T, Murabito JM, Richards JB, Rivadeneira F, Langenberg C, Perry JRB, Wareham NJ, Scott RA. Large-scale GWAS identifies multiple loci for hand grip strength providing biological insights into muscular fitness. Nat Commun 2017; 8:16015. [PMID: 29313844 PMCID: PMC5510175 DOI: 10.1038/ncomms16015] [Citation(s) in RCA: 109] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Accepted: 05/22/2017] [Indexed: 02/02/2023] Open
Abstract
Hand grip strength is a widely used proxy of muscular fitness, a marker of frailty, and predictor of a range of morbidities and all-cause mortality. To investigate the genetic determinants of variation in grip strength, we perform a large-scale genetic discovery analysis in a combined sample of 195,180 individuals and identify 16 loci associated with grip strength (P<5 × 10-8) in combined analyses. A number of these loci contain genes implicated in structure and function of skeletal muscle fibres (ACTG1), neuronal maintenance and signal transduction (PEX14, TGFA, SYT1), or monogenic syndromes with involvement of psychomotor impairment (PEX14, LRPPRC and KANSL1). Mendelian randomization analyses are consistent with a causal effect of higher genetically predicted grip strength on lower fracture risk. In conclusion, our findings provide new biological insight into the mechanistic underpinnings of grip strength and the causal role of muscular strength in age-related morbidities and mortality.
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Affiliation(s)
- Sara M. Willems
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | - Daniel J. Wright
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | - Felix R. Day
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | - Katerina Trajanoska
- Department of Internal Medicine, Erasmus Medical Center, 3015 CE Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus Medical Center, 3015 CE Rotterdam, The Netherlands
| | - Peter K. Joshi
- Usher Institute for Population Health Sciences and Informatics, University of Edinburgh, Edinburgh EH8 9AB, UK
| | - John A. Morris
- Centre for Clinical Epidemiology, Lady Davis Institute for Medical Research, Jewish General Hospital, McGill University, Montreal, Quebec, Canada QC H3T 1E2
- Department of Human Genetics, McGill University, Montreal, Quebec, Canada H3G 0B1
| | - Amy M. Matteini
- Division of Geriatric Medicine and Gerontology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA
| | - Fleur C. Garton
- Queensland Brain Institute, University of Queensland, St Lucia, Queensland 4072, Australia
| | - Niels Grarup
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Nikolay Oskolkov
- Lund University Diabetes Center, Department of Clinical Sciences, Diabetes and Endocrinology, Skånes University Hospital, 222 41 Lund, Sweden
| | - Anbupalam Thalamuthu
- Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, New South Wales 2031, Australia
| | - Massimo Mangino
- Department of Twin Research & Genetic Epidemiology, Kings College London, London SE1 7EH, UK
- NIHR Biomedical Research Centre at Guy’s and St. Thomas’ NHS Foundation Trust, London SE1 9RT, UK
| | - Jun Liu
- Department of Epidemiology, Erasmus Medical Center, 3015 CE Rotterdam, The Netherlands
| | - Ayse Demirkan
- Department of Epidemiology, Erasmus Medical Center, 3015 CE Rotterdam, The Netherlands
- Department of Human Genetics, Leiden University Medical Center, 2333 ZA Leiden, The Netherlands
| | - Monkol Lek
- Analytic and Translational Genetics Unit, Massachusetts General Hospital, Boston, Maryland 02114, USA
- Harvard Medical School, Boston, Maryland 02115, USA
| | - Liwen Xu
- Analytic and Translational Genetics Unit, Massachusetts General Hospital, Boston, Maryland 02114, USA
- Harvard Medical School, Boston, Maryland 02115, USA
| | - Guan Wang
- Centre for Sport and Exercise Science and Medicine (SESAME), University of Brighton, Eastbourne BN20 7SN, UK
| | | | - Kyle J. Gaulton
- Department of Pediatrics, University of California San Diego, La Jolla, California 92093, USA
| | - Luca A. Lotta
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | - Eri Miyamoto-Mikami
- Japan Society for the Promotion of Science, Tokyo 102-0083, Japan
- Department of Sports and Life Science, National Institute of Fitness and Sports, Kanoya, Kagoshima 891-2393, Japan
| | - Manuel A. Rivas
- Department of Biomedical Data Sciences, Stanford University, Stanford, California 94305, USA
- BROAD Institute of the Massachusetts Institute of Technology and Harvard University, Cambridge, Massachusetts 02142, USA
| | - Tom White
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | - Po-Ru Loh
- BROAD Institute of the Massachusetts Institute of Technology and Harvard University, Cambridge, Massachusetts 02142, USA
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115, USA
| | - Mette Aadahl
- Research Centre for Prevention and Health, Capital Region of Denmark, Glostrup University Hospital, DK-2600 Glostrup, Denmark
| | - Najaf Amin
- Department of Epidemiology, Erasmus Medical Center, 3015 CE Rotterdam, The Netherlands
| | - John R. Attia
- Hunter Medical Research Institute, Newcastle, New South Wales 2305, Australia
- Faculty of Health and Medicine, University of Newcastle, Newcastle, New South Wales 2308, Australia
- John Hunter Hospital, New Lambton, New South Wales 2305, Australia
| | - Krista Austin
- Centre for Sport and Exercise Science and Medicine (SESAME), University of Brighton, Eastbourne BN20 7SN, UK
| | - Beben Benyamin
- Queensland Brain Institute, University of Queensland, St Lucia, Queensland 4072, Australia
- Institute for Molecular Bioscience, University of Queensland, St Lucia, Queensland 4072, Australia
| | - Søren Brage
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | - Yu-Ching Cheng
- Division of Endocrinology Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland 21201, USA
| | - Paweł Cięszczyk
- Faculty of Physical Education, Gdańsk University of Physical Education and Sport, 80-336 Gdańsk, Poland
| | - Wim Derave
- Department of Movement and Sports Sciences, Ghent University, 9000 Ghent, Belgium
| | - Karl-Fredrik Eriksson
- Lund University Diabetes Center, Department of Clinical Sciences, Diabetes and Endocrinology, Skånes University Hospital, 222 41 Lund, Sweden
| | - Nir Eynon
- Institute of Sport, Exercise & Active Living (ISEAL), Victoria University, Melbourne, Victoria 8001, Australia
- Murdoch Children’s Research Institute, Royal Children’s Hospital, Melbourne, Victoria 3052, Australia
| | - Allan Linneberg
- Research Centre for Prevention and Health, Capital Region of Denmark, Glostrup University Hospital, DK-2600 Glostrup, Denmark
- Department of Clinical Experimental Research, Rigshospitalet, 2600 Glostrup, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - Alejandro Lucia
- Universidad Europea de Madrid, 28670 Villaviciosa de Odón, Madrid, Spain
- Research Institute ‘i+12’, Hospital Universitario 12 de Octubre, 28041 Madrid, Spain
| | - Myosotis Massidda
- Department of Life and Environmental Sciences, University of Cagliari, 09124 Cagliari, Italy
| | - Braxton D. Mitchell
- Division of Endocrinology Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland 21201, USA
- Geriatrics Research and Education Clinical Center, Baltimore Veterans Administration Medical Center, Baltimore, Maryland 21201, USA
| | - Motohiko Miyachi
- National Institutes of Biomedical Innovation, Health and Nutrition, Tokyo 162-8636, Japan
| | - Haruka Murakami
- National Institutes of Biomedical Innovation, Health and Nutrition, Tokyo 162-8636, Japan
| | - Sandosh Padmanabhan
- British Heart Foundation Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK
| | - Ashutosh Pandey
- Target Sciences, GlaxoSmithKline, King of Prussia, Pennsylvania 19406, USA
| | - Ioannis Papadimitriou
- Institute of Sport, Exercise & Active Living (ISEAL), Victoria University, Melbourne, Victoria 8001, Australia
| | - Deepak K. Rajpal
- Target Sciences, GlaxoSmithKline, King of Prussia, Pennsylvania 19406, USA
| | - Craig Sale
- Musculoskeletal Physiology Research Group, Sport, Health and Performance Enhancement (SHAPE) Research Centre, Nottingham Trent University, Nottingham NG1 4FQ, UK
| | - Theresia M. Schnurr
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Francesco Sessa
- Department of Clinical and Experimental Medicine, Medical Genetics, University of Foggia, 71122 Foggia FG, Italy
| | - Nick Shrine
- Department of Health Sciences, University of Leicester, Leicester LE1 7RH, UK
- National Institute for Health Research, Leicester Respiratory Biomedical Research Unit, Glenfield Hospital, Leicester LE3 9QP, UK
| | - Martin D. Tobin
- Department of Health Sciences, University of Leicester, Leicester LE1 7RH, UK
- National Institute for Health Research, Leicester Respiratory Biomedical Research Unit, Glenfield Hospital, Leicester LE3 9QP, UK
| | - Ian Varley
- Musculoskeletal Physiology Research Group, Sport, Health and Performance Enhancement (SHAPE) Research Centre, Nottingham Trent University, Nottingham NG1 4FQ, UK
| | - Louise V. Wain
- Department of Health Sciences, University of Leicester, Leicester LE1 7RH, UK
- National Institute for Health Research, Leicester Respiratory Biomedical Research Unit, Glenfield Hospital, Leicester LE3 9QP, UK
| | - Naomi R. Wray
- Queensland Brain Institute, University of Queensland, St Lucia, Queensland 4072, Australia
- Institute for Molecular Bioscience, University of Queensland, St Lucia, Queensland 4072, Australia
| | - Cecilia M. Lindgren
- BROAD Institute of the Massachusetts Institute of Technology and Harvard University, Cambridge, Massachusetts 02142, USA
- The Big Data Institute, University of Oxford, Oxford OX3 7BN, UK
- Wellcome Trust Centre for Human Genetics, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7BN, UK
| | - Daniel G. MacArthur
- Analytic and Translational Genetics Unit, Massachusetts General Hospital, Boston, Maryland 02114, USA
- BROAD Institute of the Massachusetts Institute of Technology and Harvard University, Cambridge, Massachusetts 02142, USA
| | - Dawn M. Waterworth
- Target Sciences, GlaxoSmithKline, King of Prussia, Pennsylvania 19406, USA
| | - Mark I. McCarthy
- Wellcome Trust Centre for Human Genetics, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7BN, UK
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Oxford OX3 7LE, UK
- NIHR Oxford Biomedical Research Centre, Oxford OX3 7LE, UK
| | - Oluf Pedersen
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Kay-Tee Khaw
- Department of Public Health and Primary Care, University of Cambridge, Cambridge CB2 0SR, UK
| | - Douglas P. Kiel
- Harvard Medical School, Boston, Maryland 02115, USA
- Institute for Aging Research, Hebrew SeniorLife, Boston, Massachusetts 02131, USA
- Department of Medicine, Beth Israel Deaconess Medical Centre, Boston, Massachusetts 02215, USA
| | - Yannis Pitsiladis
- Centre for Sport and Exercise Science and Medicine (SESAME), University of Brighton, Eastbourne BN20 7SN, UK
| | - Noriyuki Fuku
- Graduate School of Health and Sports Science, Juntendo University, Chiba 270-1695, Japan
| | - Paul W. Franks
- Genetic and Molecular Epidemiology Unit, Department of Clinical Sciences, Lund University, Skånes University Hospital, 222 41 Lund, Sweden
- Public Health and Clinical Medicine, Section for Medicine, Umeå University, 901 87 Umeå, Sweden
- Biobank Research, Umeå University, 901 87 Umeå, Sweden
| | - Kathryn N. North
- Murdoch Children’s Research Institute, Royal Children’s Hospital, Melbourne, Victoria 3052, Australia
| | - Cornelia M. van Duijn
- Department of Epidemiology, Erasmus Medical Center, 3015 CE Rotterdam, The Netherlands
| | - Karen A. Mather
- Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, New South Wales 2031, Australia
| | - Torben Hansen
- The Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
- Faculty of Health Sciences, University of Southern Denmark, 5230 Odense M, Denmark
| | - Ola Hansson
- Lund University Diabetes Center, Department of Clinical Sciences, Diabetes and Endocrinology, Skånes University Hospital, 222 41 Lund, Sweden
| | - Tim Spector
- Department of Twin Research & Genetic Epidemiology, Kings College London, London SE1 7EH, UK
| | - Joanne M. Murabito
- Boston University School of Medicine, Department of Medicine, Section of General Internal Medicine, Boston, Massachusetts 02118, USA
- National Heart Lung and Blood Institute’s and Boston University’s Framingham Heart Study, Framingham, Massachusetts 01702, USA
| | - J. Brent Richards
- Centre for Clinical Epidemiology, Lady Davis Institute for Medical Research, Jewish General Hospital, McGill University, Montreal, Quebec, Canada QC H3T 1E2
- Department of Human Genetics, McGill University, Montreal, Quebec, Canada H3G 0B1
- Department of Twin Research & Genetic Epidemiology, Kings College London, London SE1 7EH, UK
- Department of Medicine, McGill University, Montreal, Quebec, Canada H3G 1A4
| | - Fernando Rivadeneira
- Department of Internal Medicine, Erasmus Medical Center, 3015 CE Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus Medical Center, 3015 CE Rotterdam, The Netherlands
| | - Claudia Langenberg
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | - John R. B. Perry
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | - Nick J. Wareham
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | - Robert A. Scott
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
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Karki P, Johnson J, Son DS, Aschner M, Lee E. Transcriptional Regulation of Human Transforming Growth Factor-α in Astrocytes. Mol Neurobiol 2016; 54:964-976. [PMID: 26797516 DOI: 10.1007/s12035-016-9705-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 01/05/2016] [Indexed: 11/25/2022]
Abstract
Transforming growth factor-alpha (TGF-α) is known to play multifunctional roles in the central nervous system (CNS), including the provision of neurotropic properties that protect neurons against various neurotoxic insults. Previously, we reported that TGF-α mediates estrogen-induced enhancement of glutamate transporter GLT-1 function in astrocytes. However, the regulatory mechanism of TGF-α at the transcriptional level remains to be established. Our findings revealed that the human TGF-α promoter contains consensus sites for several transcription factors, such as NF-κB and yin yang 1 (YY1). NF-κB served as a positive regulator of TGF-α promoter activity, corroborated by observations that overexpression of NF-κB p65 increased, while mutation in the NF-κB binding sites in the TGF-α promoter reduced the promoter activity in rat primary astrocytes. Pharmacological inhibition of NF-κB with pyrrolidine dithiocarbamate (PDTC; 50 μM) or quinazoline (QNZ; 10 μM) also abolished TGF-α promoter activity, and NF-κB directly bound to its consensus site in the TGF-α promoter as evidenced by electrophoretic mobility shift assay (EMSA). Dexamethasone (DX) increased TGF-α promoter activity by activation of NF-κB. Treatment of astrocytes with 100 nM of DX for 24 h activated its glucocorticoid receptor and signaling proteins, including MAPK, PI3K/Akt, and PKA, via non-genomic pathways, to enhance TGF-α promoter activity and expression. YY1 served as a critical negative regulator of the TGF-α promoter as overexpression of YY1 decreased, while mutation of YY1 binding site in the promoter increased TGF-α promoter activity. Treatment for 3 h with 250 μM of manganese (Mn), an environmental neurotoxin, decreased astrocytic TGF-α expression by activation of YY1. Taken together, our results suggest that NF-κB is a critical positive regulator, whereas YY1 is a negative regulator of the TGF-α promoter. These findings identify potential molecular targets for neurotherapeutics that may modulate TGF-α regulation and afford neuroprotection.
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Affiliation(s)
- Pratap Karki
- Department of Physiology, School of Medicine, Meharry Medical College, Nashville, TN, 37208, USA
| | - James Johnson
- Department of Physiology, School of Medicine, Meharry Medical College, Nashville, TN, 37208, USA
| | - Deok-Soo Son
- Department of Physiology, School of Medicine, Meharry Medical College, Nashville, TN, 37208, USA
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Eunsook Lee
- Department of Physiology, School of Medicine, Meharry Medical College, Nashville, TN, 37208, USA.
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11
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Avraham HK, Jiang S, Fu Y, Rockenstein E, Makriyannis A, Wood J, Wang L, Masliah E, Avraham S. Impaired neurogenesis by HIV-1-Gp120 is rescued by genetic deletion of fatty acid amide hydrolase enzyme. Br J Pharmacol 2015; 172:4603-14. [PMID: 24571443 PMCID: PMC4594266 DOI: 10.1111/bph.12657] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2013] [Revised: 02/03/2014] [Accepted: 02/11/2014] [Indexed: 01/14/2023] Open
Abstract
Background and Purpose The HIV-envelope glycoprotein Gp120 is involved in neuronal injury and is associated with neuro-AIDS pathogenesis in the brain. Endocannabinoids are important lipid ligands in the CNS regulating neural functions, and their degeneration is controlled by hydrolysing enzymes such as the fatty acid amide hydrolase (FAAH). Here, we examined whether in vivo genetic deletion of Faah gene prevents HIV-1 Gp120-mediated effects on neurogenesis. Experimental Approach We generated new GFAP/Gp120 transgenic (Tg) mice that have genetic deletion of Faah gene by mating glial fribillary acidic protein (GFAP)/Gp120 Tg mice with Faah−/− mice. Neurogenesis and cell death were assessed by immunocytochemical analysis. Key Results Endocannabinoid levels in the brain of the double GFAP/Gp120//Faah−/− mice were similar to those observed in Faah−/− mice. However, unlike the impaired neurogenesis observed in GFAP/Gp120 Tg mice and Faah−/− mice, these GFAP/Gp120//Faah-/ mice showed significantly improved neurogenesis in the hippocampus, indicated by a significant increase in neuroblasts and neuronal cells, an increase in BrdU+ cells and doublecortin positive cells (DCX+), and an increase in the number of PCNA. Furthermore, a significant decrease in astrogliosis and gliogenesis was observed in GFAP/Gp120//Faah−/−mice and neurogenesis was stimulated by neural progenitor cells (NPCs) and/or the newly formed NPC niches characterized by increased COX-2 expression and elevated levels of PGE2. Conclusions and Implications In vivo genetic ablation of Faah, resulted in enhanced neurogenesis through modulation of the newly generated NPC niches in GFAP/Gp120//Faah−/− mice. This suggests a novel approach of using FAAH inhibitors to enhance neurogenesis in HIV-1 infected brain.
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Affiliation(s)
- H K Avraham
- Division of Experimental Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA.,Center for Drug Discovery, Northeastern University, Boston, MA, USA
| | - S Jiang
- Division of Experimental Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA
| | - Y Fu
- Division of Experimental Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA
| | - E Rockenstein
- Department of Neurosciences and Pathology, School of Medicine, University of California San Diego, La Jolla, CA, USA
| | - A Makriyannis
- Center for Drug Discovery, Northeastern University, Boston, MA, USA
| | - J Wood
- Center for Drug Discovery, Northeastern University, Boston, MA, USA
| | - L Wang
- Division of Experimental Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA
| | - E Masliah
- Department of Neurosciences and Pathology, School of Medicine, University of California San Diego, La Jolla, CA, USA
| | - S Avraham
- Division of Experimental Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA
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12
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Yu Y, Chen H, Su SB. Neuroinflammatory responses in diabetic retinopathy. J Neuroinflammation 2015; 12:141. [PMID: 26245868 PMCID: PMC4527131 DOI: 10.1186/s12974-015-0368-7] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Accepted: 07/27/2015] [Indexed: 01/14/2023] Open
Abstract
Diabetic retinopathy (DR) is a common complication of diabetes and has been recognized as a vascular dysfunction leading to blindness in working-age adults. It becomes increasingly clear that neural cells in retina play an important role in the pathogenesis of DR. Neural retina located at the back of the eye is part of the brain and a representative of the central nervous system. The neurosensory deficits seen in DR are related to inflammation and occur prior to the clinically identifiable vascular complications. The neural deficits are associated with abnormal reactions of retina glial cells and neurons in response to hyperglycemia. Improper activation of the innate immune system may also be an important contributor to the pathophysiology of DR. Therefore, DR manifests characteristics of both vasculopathy and chronic neuroinflammatory diseases. In this article, we attempt to provide an overview of the current understanding of inflammation in neural retina abnormalities in diabetes. Inhibition of neuroinflammation may represent a novel therapeutic strategy to the prevention of the progression of DR.
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Affiliation(s)
- Ying Yu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, 54 S Xianlie Road, Guangzhou, 510060, China.
| | - Hui Chen
- Eye Institute, Affiliated Hospital of Nantong University, Nantong, 226001, China.
| | - Shao Bo Su
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, 54 S Xianlie Road, Guangzhou, 510060, China.
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13
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M K. Present and New Treatment Strategies in the Management of Glaucoma. Open Ophthalmol J 2015; 9:89-100. [PMID: 26069521 PMCID: PMC4460216 DOI: 10.2174/1874364101509010089] [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] [Subscribe] [Scholar Register] [Received: 03/28/2015] [Revised: 03/30/2015] [Accepted: 03/30/2015] [Indexed: 12/17/2022] Open
Abstract
Glaucoma is a neurodegenerative disease characterized by retinal ganglion cell (RGC) death and axonal loss. It remains a major cause of blindness worldwide. All current modalities of treatment are focused on lowering intraocular pressure (IOP), and it is evident that increased IOP is an important risk factor for progression of the disease. However, it is clear that a significant number of glaucoma patients show disease progression despite of pressure lowering treatments. Much attention has been given to the development of neuroprotective treatment strategies, but the identification of such has been hampered by lack of understanding of the etiology of glaucoma. Hence, in spite of many attempts no neuroprotective drug has yet been clinically approved. Even though neuroprotection is without doubt an important treatment strategy, many glaucoma subjects are diagnosed after substantial loss of RGCs. In this matter, recent approaches aim to rescue RGCs and regenerate axons in order to restore visual function in glaucoma. The present review seeks to provide an overview of the present and new treatment strategies in the management of glaucoma. The treatment strategies are divided into current available glaucoma medications, new pressure lowering targets, prospective neuroprotective interventions, and finally possible neuroregenrative strategies.
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Affiliation(s)
- Kolko M
- Department of Neuroscience and Pharmacology, the Panum Institute, University of Copenhagen, Denmark ; Department of Ophthalmology, Roskilde University Hospital, Copenhagen, Denmark ; Center of Healthy Aging, Department of Cellular and Molecular Medicine, the Panum Institute, University of Copenhagen, Denmark
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14
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Detection of mouse endogenous type B astrocytes migrating towards brain lesions. Stem Cell Res 2015; 14:114-29. [PMID: 25564310 DOI: 10.1016/j.scr.2014.11.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2014] [Revised: 11/17/2014] [Accepted: 11/24/2014] [Indexed: 11/24/2022] Open
Abstract
Neuroblasts represent the predominant migrating cell type in the adult mouse brain. There are, however, increasing evidences of migration of other neural precursors. This work aims at identifying in vivo endogenous early neural precursors, different from neuroblasts, able to migrate in response to brain injuries. The monoclonal antibody Nilo1, which unequivocally identifies type B astrocytes and embryonic radial glia, was coupled to magnetic glyconanoparticles (mGNPs). Here we show that Nilo1-mGNPs in combination with magnetic resonance imaging in living mice allowed the in vivo identification of endogenous type B astrocytes at their niche, as well as their migration to the lesion site in response to glioblastoma, demyelination, cryolesion or mechanical injuries. In addition, Nilo1(+) adult radial glia-like structures were identified at the lesion site a few hours after damage. For all damage models used, type B astrocyte migration was fast and orderly. Identification of Nilo1(+) cells surrounding an induced glioblastoma was also possible after intraperitoneal injection of the antibody. This opens up the possibility of an early identification of the initial damage site(s) after brain insults, by the migration of type B astrocytes.
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15
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Karki P, Smith K, Johnson J, Lee E. Astrocyte-derived growth factors and estrogen neuroprotection: role of transforming growth factor-α in estrogen-induced upregulation of glutamate transporters in astrocytes. Mol Cell Endocrinol 2014; 389:58-64. [PMID: 24447465 PMCID: PMC4040305 DOI: 10.1016/j.mce.2014.01.010] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Revised: 01/09/2014] [Accepted: 01/09/2014] [Indexed: 01/31/2023]
Abstract
Extensive studies from the past decade have completely revolutionized our understanding about the role of astrocytes in the brain from merely supportive cells to an active role in various physiological functions including synaptic transmission via cross-talk with neurons and neuroprotection via releasing neurotrophic factors. Particularly, numerous studies have reported that astrocytes mediate the neuroprotective effects of 17β-estradiol (E2) and selective estrogen receptor modulators (SERMs) in various clinical and experimental models of neuronal injury. Astrocytes contain two main glutamate transporters, glutamate aspartate transporter (GLAST) and glutamate transporter-1 (GLT-1), that play a key role in preventing excitotoxic neuronal death, a process associated with most neurodegenerative diseases. E2 has been shown to increase expression of both GLAST and GLT-1 mRNA and protein and glutamate uptake in astrocytes. Growth factors such as transforming growth factor-α (TGF-α) appear to mediate E2-induced enhancement of these transporters. These findings suggest that E2 exerts neuroprotection against excitotoxic neuronal injuries, at least in part, by enhancing astrocytic glutamate transporter levels and function. Therefore, the present review will discuss proposed mechanisms involved in astrocyte-mediated E2 neuroprotection, with a focus on glutamate transporters.
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Affiliation(s)
- Pratap Karki
- Department of Physiology, School of Medicine, Meharry Medical College, Nashville, TN, USA
| | - Keisha Smith
- Department of Physiology, School of Medicine, Meharry Medical College, Nashville, TN, USA
| | - James Johnson
- Department of Physiology, School of Medicine, Meharry Medical College, Nashville, TN, USA
| | - Eunsook Lee
- Department of Physiology, School of Medicine, Meharry Medical College, Nashville, TN, USA.
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16
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Chua B, Goldberg I. Neuroprotective agents in glaucoma therapy: recent developments and future directions. EXPERT REVIEW OF OPHTHALMOLOGY 2014. [DOI: 10.1586/eop.10.55] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Fang KM, Yang CS, Lin TC, Chan TC, Tzeng SF. Induced interleukin-33 expression enhances the tumorigenic activity of rat glioma cells. Neuro Oncol 2013; 16:552-66. [PMID: 24327583 DOI: 10.1093/neuonc/not234] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND Glioma development is a multistep process associated with progressive genetic alterations but also regulated by cellular and noncellular components in a tumor-associated niche. METHODS Using 2 rat C6 glioma cell clones with different tumorigenesis, named C6-1 and C6-2, this study characterized genes associated with enhanced tumorigenic features of glioma cells by comparative cDNA microarray analysis combined with Q-PCR. Neurospehere formation and clonogenicity were examined to determine the growth of tumorigenic C6 glioma cells. The lentivirus-mediated gene knockdown approach was conducted to determine the role of interleukin-33 (IL-33) in glioma cell proliferation and migration. Transwell cell invasion assay was used to examine microglia migration induced by tumorigenic C6 cells. RESULTS The functional analysis of gene ontology (GO) biological processes shows that the upregulated genes found in tumorigenic C6 (C6-1) cells are closely related to cell proliferation. Tumorigenic C6 cells expressed cytokines and chemokines abundantly. Among these genes, IL-33 was profoundly induced in tumorigenic C6 cells with the expression of IL-33 receptor ST2. Furthermore, the growth rate and colony formation of tumorigenic C6 cells were attenuated by the inhibition of IL-33 and ST2 gene expression. Moreover, IL-33 was involved in tumorigenic glioma cell migration and regulation of the expression of several glioma-associated growth factors and chemokines in tumorigenic C6 cells. CONCLUSION Accordingly, we concluded that glioma cells with abundant production of IL-33 grow rapidly; moreover, the interactions of multiple cytokines/chemokines induced by glioma cells may develop a microenvironment that facilitates microglia/macrophage infiltration and fosters glioma growth in the brain.
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Affiliation(s)
- Kuan-Min Fang
- Department of Life Sciences, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan City, Taiwan (K.M.F., T.C.L., T.C.C., S.F.T.); Center for Nanomedicine Research, National Health Research Institutes, Zhunan, Taiwan (C.S.Y.)
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18
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Lemcke H, Kuznetsov SA. Involvement of connexin43 in the EGF/EGFR signalling during self-renewal and differentiation of neural progenitor cells. Cell Signal 2013; 25:2676-84. [DOI: 10.1016/j.cellsig.2013.08.030] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 08/26/2013] [Accepted: 08/28/2013] [Indexed: 10/26/2022]
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19
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Gao Z, Zhu Q, Zhang Y, Zhao Y, Cai L, Shields CB, Cai J. Reciprocal modulation between microglia and astrocyte in reactive gliosis following the CNS injury. Mol Neurobiol 2013; 48:690-701. [PMID: 23613214 DOI: 10.1007/s12035-013-8460-4] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Accepted: 04/09/2013] [Indexed: 12/16/2022]
Abstract
Reactive gliosis, also known as glial scar formation, is an inflammatory response characterized by the proliferation of microglia and astrocytes as well as astrocytic hypertrophy following injury in the central nervous system (CNS). The glial scar forms a physical and molecular barrier to isolate the injured area from adjacent normal nervous tissue for re-establishing the integrity of the CNS. It prevents the further spread of cellular damage but represents an obstacle to regrowing axons. In this review, we integrated the current findings to elucidate the tightly reciprocal modulation between activated microglia and astrocytes in reactive gliosis and proposed that modification of cellular response to the injury or cellular reprogramming in the glial scar could lead advances in axon regeneration and functional recovery after the CNS injury.
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Affiliation(s)
- Zhongwen Gao
- Department of Spine Surgery, the First Hospital of Jilin University, 71 Xinmin Street, Changchun, Jilin, 130021, China
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20
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Mutti E, Lildballe DL, Kristensen L, Birn H, Nexo E. Vitamin B₁₂ dependent changes in mouse spinal cord expression of vitamin B₁₂ related proteins and the epidermal growth factor system. Brain Res 2013; 1503:1-6. [PMID: 23399680 DOI: 10.1016/j.brainres.2013.01.050] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Revised: 01/28/2013] [Accepted: 01/31/2013] [Indexed: 12/13/2022]
Abstract
Chronic vitamin B12 (cobalamin) deficiency in the mammalian central nervous system causes degenerative damage, especially in the spinal cord. Previous studies have shown that cobalamin status alters spinal cord expression of epidermal growth factor (EGF) and its receptor in rats. Employing a mouse model of cobalamin-depletion and loading, we have explored the influence of Cbl status on spinal cord expression of cobalamin related proteins, as well as all four known EGF receptors and their activating ligands. Following four weeks of osmotic minipump infusion (n=7 in each group) with cobinamide (4.25nmol/h), saline or cobalamin (1.75nmol/h) the spinal cords were analyzed for cobalamin and for the mRNA levels of cobalamin related proteins and members of the EGF system using quantitative reverse transcription PCR. The median spinal cord cobalamin content was 17, 32, and 52pmol/gr of tissues in cobinamide, saline, and cobalamin treated animals, respectively. Both cobinamide and cobalamin induced a significant decrease in the expression of the lysosomal membrane cobalamin transporter. All four EGF receptors and their activating ligands, except for EGF, were expressed in the spinal cord. Notably, the expression of one of the EGF receptors, HER3, and the ligands heparin-binding EGF-like growth factor, transforming growth factor-α, and neuregulins 1α was increased in cobalamin treated mice. Our studies show that four weeks treatment of mice with cobinamide induces spinal cord cobalamin depletion and that cobalamin loading induces an altered expression pattern of the EGF system thus confirming a spinal cord cross talk between Cbl and the EGF system.
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Affiliation(s)
- Elena Mutti
- Department of Clinical Biochemistry, Aarhus University Hospital, Norrebrogade 44, DK-8000 Aarhus, Denmark.
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21
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Lee E, Sidoryk-Wegrzynowicz M, Farina M, Rocha JBT, Aschner M. Estrogen attenuates manganese-induced glutamate transporter impairment in rat primary astrocytes. Neurotox Res 2012; 23:124-30. [PMID: 22878846 DOI: 10.1007/s12640-012-9347-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2012] [Revised: 07/26/2012] [Accepted: 07/30/2012] [Indexed: 10/28/2022]
Abstract
The astrocytic glutamate transporters (GLT-1, GLAST) are critical for removing excess glutamate from synaptic sites, thereby maintaining glutamate homeostasis within the brain. 17β-Estradiol (E2) is one of the most active estrogen hormones possessing neuroprotective effects both in in vivo and in vitro models, and it has been shown to enhance astrocytic glutamate transporter function (Liang et al. in J Neurochem 80:807-814, 2002; Pawlak et al. in Brain Res Mol Brain Res 138:1-7, 2005). However, E2 is not clinically optimal for neuroprotection given its peripheral feminizing and proliferative effects; therefore, brain selective estrogen receptor modulators (neuro SERMs) (Zhao et al. in Neuroscience 132:299-311, 2005) that specifically target estrogenic mechanisms, but lack the systemic estrogen side effects offer more promising therapeutic modality for the treatment of conditions associated with excessive synaptic glutamate levels. This review highlights recent studies from our laboratory showing that E2 and SERMs effectively reverse glutamate transport inhibition in a manganese (Mn)-induced model of glutamatergic deregulation. Specifically, we discuss mechanisms by which E2 restores the expression and activity of glutamate uptake. We advance the hypothesis that E2 and related compounds, such as tamoxifen may offer a potential therapeutic modality in neurodegenerative disorders, which are characterized by altered glutamate homeostasis.
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Affiliation(s)
- Eunsook Lee
- Department of Physiology, Meharry Medical College, Nashville, TN 37208, USA.
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22
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Thirant C, Galan-Moya EM, Dubois LG, Pinte S, Chafey P, Broussard C, Varlet P, Devaux B, Soncin F, Gavard J, Junier MP, Chneiweiss H. Differential proteomic analysis of human glioblastoma and neural stem cells reveals HDGF as a novel angiogenic secreted factor. Stem Cells 2012; 30:845-53. [PMID: 22331796 DOI: 10.1002/stem.1062] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Presence in glioblastomas of cancer cells with normal neural stem cell (NSC) properties, tumor initiating capacity, and resistance to current therapies suggests that glioblastoma stem-like cells (GSCs) play central roles in glioblastoma development. We cultured human GSCs endowed with all features of tumor stem cells, including tumor initiation after xenograft and radio-chemoresistance. We established proteomes from four GSC cultures and their corresponding whole tumor tissues (TTs) and from human NSCs. Two-dimensional difference gel electrophoresis and tandem mass spectrometry revealed a twofold increase of hepatoma-derived growth factor (HDGF) in GSCs as compared to TTs and NSCs. Western blot analysis confirmed HDGF overexpression in GSCs as well as its presence in GSC-conditioned medium, while, in contrast, no HDGF was detected in NSC secretome. At the functional level, GSC-conditioned medium induced migration of human cerebral endothelial cells that can be blocked by anti-HDGF antibodies. In vivo, GSC-conditioned medium induced neoangiogenesis, whereas HDGF-targeting siRNAs abrogated this effect. Altogether, our results identify a novel candidate, by which GSCs can support neoangiogenesis, a high-grade glioma hallmark. Our strategy illustrates the usefulness of comparative proteomic analysis to decipher molecular pathways, which underlie GSC properties.
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Affiliation(s)
- Cécile Thirant
- INSERM U894, Psychiatry and Neuroscience Center, Glial Plasticity Team, Cochin Institute, Paris Descartes University, Paris, France
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23
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Romero-Grimaldi C, Murillo-Carretero M, López-Toledano MA, Carrasco M, Castro C, Estrada C. ADAM-17/tumor necrosis factor-α-converting enzyme inhibits neurogenesis and promotes gliogenesis from neural stem cells. Stem Cells 2012; 29:1628-39. [PMID: 21837653 DOI: 10.1002/stem.710] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Neural precursor cells (NPCs) are activated in central nervous system injury. However, despite being multipotential, their progeny differentiates into astrocytes rather than neurons in situ. We have investigated the role of epidermal growth factor receptor (EGFR) in the generation of non-neurogenic conditions. Cultured mouse subventricular zone NPCs exposed to differentiating conditions for 4 days generated approximately 50% astrocytes and 30% neuroblasts. Inhibition of EGFR with 4-(3-chloroanilino)-6,7-dimethoxyquinazoline significantly increased the number of neuroblasts and decreased that of astrocytes. The same effects were observed upon treatment with the metalloprotease inhibitor galardin, N-[(2R)-2-(hydroxamidocarbonylmethyl)-4-methylpentanoyl]-L-tryptophan methylamide (GM 6001), which prevented endogenous transforming growth factor-α (TGF-α) release. These results suggested that metalloprotease-dependent EGFR-ligand shedding maintained EGFR activation and favored gliogenesis over neurogenesis. Using a disintegrin and metalloprotease 17 (ADAM-17) small interference RNAs transfection of NPCs, ADAM-17 was identified as the metalloprotease involved in cell differentiation in these cultures. In vivo experiments revealed a significant upregulation of ADAM-17 mRNA and de novo expression of ADAM-17 protein in areas of cortical injury in adult mice. Local NPCs, identified by nestin staining, expressed high levels of ADAM-17, as well as TGF-α and EGFR, the three molecules necessary to prevent neurogenesis and promote glial differentiation in vitro. Chronic local infusions of GM6001 resulted in a notable increase in the number of neuroblasts around the lesion. These results indicate that, in vivo, the activation of a metalloprotease, most probably ADAM-17, initiates EGFR-ligand shedding and EGFR activation in an autocrine manner, preventing the generation of new neurons from NPCs. Inhibition of ADAM-17, the limiting step in this sequence, may contribute to the generation of neurogenic niches in areas of brain damage.
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Abstract
Although rodent models have been essential to unveil the emerging functions of astrocytes, the existence of interspecies differences calls for caution in extrapolating data from rodent to human astrocytes. We have developed highly enriched primary astrocyte cultures from human fetuses and adult cerebro-cortical biopsies from neurosurgery patients. Immunocytochemical characterization shows that cultures are composed of more than 95% of cells expressing in vitro astrocytic markers. Examination of the morphological and proliferative properties of cultures derived from the cerebral cortex and the hypothalamus both in untreated conditions and after treatment with EGF-related ligands illustrates the high plasticity of human astrocytes and their functional heterogeneity according to the cerebral region of origin. Our preparation offers the opportunity to characterize human astrocyte functions in vitro and also provides a valuable tool for studying the functional heterogeneity of human astrocytes isolated from distinct brain regions.
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25
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Lai Y, Asthana A, Cheng K, Kisaalita WS. Neural cell 3D microtissue formation is marked by cytokines' up-regulation. PLoS One 2011; 6:e26821. [PMID: 22046371 PMCID: PMC3203927 DOI: 10.1371/journal.pone.0026821] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2011] [Accepted: 10/05/2011] [Indexed: 01/04/2023] Open
Abstract
Cells cultured in three dimensional (3D) scaffolds as opposed to traditional two-dimensional (2D) substrates have been considered more physiologically relevant based on their superior ability to emulate the in vivo environment. Combined with stem cell technology, 3D cell cultures can provide a promising alternative for use in cell-based assays or biosensors in non-clinical drug discovery studies. To advance 3D culture technology, a case has been made for identifying and validating three-dimensionality biomarkers. With this goal in mind, we conducted a transcriptomic expression comparison among neural progenitor cells cultured on 2D substrates, 3D porous polystyrene scaffolds, and as 3D neurospheres (in vivo surrogate). Up-regulation of cytokines as a group in 3D and neurospheres was observed. A group of 13 cytokines were commonly up-regulated in cells cultured in polystyrene scaffolds and neurospheres, suggesting potential for any or a combination from this list to serve as three-dimensionality biomarkers. These results are supportive of further cytokine identification and validation studies with cells from non-neural tissue.
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Affiliation(s)
- Yinzhi Lai
- Cellular Bioengineering Laboratory, Department of Biological and Agricultural Engineering, Faculty of Engineering, Driftmier Engineering Center, University of Georgia, Athens, Georgia, United States of America
| | - Amish Asthana
- Cellular Bioengineering Laboratory, Department of Biological and Agricultural Engineering, Faculty of Engineering, Driftmier Engineering Center, University of Georgia, Athens, Georgia, United States of America
| | - Ke Cheng
- Cellular Bioengineering Laboratory, Department of Biological and Agricultural Engineering, Faculty of Engineering, Driftmier Engineering Center, University of Georgia, Athens, Georgia, United States of America
| | - William S. Kisaalita
- Cellular Bioengineering Laboratory, Department of Biological and Agricultural Engineering, Faculty of Engineering, Driftmier Engineering Center, University of Georgia, Athens, Georgia, United States of America
- * E-mail:
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26
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Junier MP, Sharif A. [Instability of cell phenotype and tumor initiating cells in gliomas]. Biol Aujourdhui 2011; 205:63-74. [PMID: 21501577 DOI: 10.1051/jbio/2011002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2010] [Indexed: 05/30/2023]
Abstract
Gliomas, the most frequent primitive CNS tumors, have been suggested to originate from astrocytes or from neural progenitors/stem cells. However, the precise identity of the cells at the origin of gliomas remains a matter of debate because no pre-neoplastic state has been yet identified. TGFα, an EGF family member, is frequently over-expressed in the early stages of glioma progression. We questioned whether prolonged TGFα exposure affects the stability of the normal mature astrocyte phenotype and, eventually, their propensity to cancerous transformation. Using mouse astrocyte cultures devoid of residual neural stem cells or progenitors, we demonstrate that several days of TGFα-treatment result in the functional conversion of a population of mature astrocytes into radial glial cells, a population of neural progenitors, without any accompanying sign of cancerous transformation. In contrast, when astrocytes de-differentiated with TGFα were submitted to oncogenic stress using gamma irradiation, they acquired cancerous properties, forming high-grade glioma-like tumors after brain grafting. Gamma irradiation was without effect on astrocytes which were not treated with TGFα. These results suggested that most gliomas should contain tumor cells with stem-like properties (TSCs). Our study of 55 pediatric brain tumors show that tumor cells with stem cell-like or progenitor-like properties can be isolated from a majority of gliomas. Survival analysis showed an association between isolation of TSCs with extended self-renewal capabilities and a patient's higher mortality rate.
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Affiliation(s)
- Marie-Pierre Junier
- Inserm, UMR894, Équipe Plasticité gliale, Université Paris V, 75006 Paris, France.
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27
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Gang B, Yue C, Han N, Xue H, Li B, Sun L, Li X, Zhao Q. Limited hippocampal neurogenesis in SAMP8 mouse model of Alzheimer's disease. Brain Res 2011; 1389:183-93. [PMID: 21439270 DOI: 10.1016/j.brainres.2011.03.039] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2010] [Revised: 03/12/2011] [Accepted: 03/16/2011] [Indexed: 12/19/2022]
Abstract
Increasing adult neurogenesis in the hippocampal formation (HF) has been proposed as a potential foundation for neuronal repair in Alzheimer's disease (AD), but the evidence remains controversial. We used P8 strain of senescence-accelerated mice (SAMP8) as a model of AD to investigate changes in adult neurogenesis. We examined new proliferating cells and their survival in the dentate gyrus (DG) of the HF using 5-bromodeoxyuridine (BrdU) labeling and investigated newborn cell development and differentiation with a combination of phenotype markers. In 5-month-old SAMP8, the number of BrdU(+) cells in the DG was significantly increased relative to controls, in accordance with the rising numbers of doublecortin-positive (DCX(+)) immature neurons. Some of these BrdU(+) cells migrated to cornu ammonis 1 (CA1), possibly related to the compensation of neuronal loss. However, the capacity of neurogenesis to compensate neuronal loss during neurodegeneration was limited. First, only half of the BrdU(+) cells survived 4weeks after mitosis, and even fewer developed into neuron-specific nuclear protein positive (NeuN(+)) mature neurons. Second, the number of BrdU(+) cells and DCX(+) cells was decreased in 10-month-old SAMP8, which exhibited progressive neurodegeneration. In addition, the results provided insight into astrocytes as a crucial component of the neurogenic niche. The number of newborn astrocytes and expression of glial fibrillary acidic protein (GFAP) were diminished in the DG of SAMP8 animals, possibly explaining the insufficient neurogenesis. Thus, stimulating limited neurogenesis in AD by improving the neurogenic niche may have therapeutic potential.
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Affiliation(s)
- Baozhi Gang
- Department of Neurology, The First Clinical College, Harbin Medical University, 23rd Youzheng Street, Nangang District, Harbin, Heilongjiang Province 15001, China
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Tóth ZE, Leker RR, Shahar T, Bratincsak A, Szalayova I, Key S, Palkovits M, Cassiani-Ingoni R, Mezey E. Bone marrow-derived nonreactive astrocytes in the mouse brain after permanent middle cerebral artery occlusion. Stem Cells Dev 2010; 20:539-46. [PMID: 20604679 DOI: 10.1089/scd.2010.0237] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We studied the effect of permanent unilateral middle cerebral artery occlusion (PMCAO) on the generation of bone marrow (BM)-derived astrocytes in female mice previously transplanted with enhanced green fluorescent protein-expressing BM from male donors. In addition to an untreated PMCAO group, one group of mice also received intracerebral infusion of transforming growth factor-alpha, resulting in a decrease in the size of the infarct. Two months after PMCAO, we found a specific type of astrocyte of BM origin in the side of the injury, near the lesion. These astrocytes did not express glial fibrillary acidic protein (GFAP) by conventional fluorescence immunostaining; however, GFAP was easily detectable by tyramide signal amplification. These cells also expressed S100β, confirming their astrocytic character. Unlike the endogenous reactive astrocytes, these BM-derived astrocytes did not proliferate during the first week of ischemia and did not contribute to the glial scar formation. Transforming growth factor-alpha infusion increased the number of BM-derived astrocytes, without affecting their distribution. Interestingly, exclusively by tyramide signal amplification staining, we found that endogenous astrocytes displaying an identical morphology were also present in control mouse and human brains. Our data demonstrate that a subpopulation of nonreactive astrocytes expressing low levels of GFAP can originate from transplanted BM in the ischemic brain. We believe that these cells represent a subpopulation of astrocytes earlier considered to be GFAP negative. The high number of astrocytes with identical morphology and chemical character in control brains suggest that these type of astrocytes may have important functional role in the central nervous system that calls for further studies.
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Affiliation(s)
- Zsuzsanna E Tóth
- National Institute of Dental and Craniofacial Research, National Institute of Health, Bethesda, Maryland 20892, USA
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Genome-wide expression profiling and functional network analysis upon neuroectodermal conversion of human mesenchymal stem cells suggest HIF-1 and miR-124a as important regulators. Exp Cell Res 2010; 316:2760-78. [DOI: 10.1016/j.yexcr.2010.06.012] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2009] [Revised: 06/10/2010] [Accepted: 06/16/2010] [Indexed: 11/17/2022]
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30
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EGFR immunolabeling pattern may discriminate low-grade gliomas from gliosis. J Neurooncol 2010; 102:171-8. [DOI: 10.1007/s11060-010-0308-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2007] [Accepted: 07/08/2010] [Indexed: 10/19/2022]
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31
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Prevot V, Hanchate NK, Bellefontaine N, Sharif A, Parkash J, Estrella C, Allet C, de Seranno S, Campagne C, de Tassigny XD, Baroncini M. Function-related structural plasticity of the GnRH system: a role for neuronal-glial-endothelial interactions. Front Neuroendocrinol 2010; 31:241-58. [PMID: 20546773 DOI: 10.1016/j.yfrne.2010.05.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2010] [Revised: 05/17/2010] [Accepted: 05/18/2010] [Indexed: 12/18/2022]
Abstract
As the final common pathway for the central control of gonadotropin secretion, GnRH neurons are subjected to numerous regulatory homeostatic and external factors to achieve levels of fertility appropriate to the organism. The GnRH system thus provides an excellent model in which to investigate the complex relationships between neurosecretion, morphological plasticity and the expression of a physiological function. Throughout the reproductive cycle beginning from postnatal sexual development and the onset of puberty to reproductive senescence, and even within the ovarian cycle itself, all levels of the GnRH system undergo morphological plasticity. This structural plasticity within the GnRH system appears crucial to the timely control of reproductive competence within the individual, and as such must have coordinated actions of multiple signals secreted from glial cells, endothelial cells, and GnRH neurons. Thus, the GnRH system must be viewed as a complete neuro-glial-vascular unit that works in concert to maintain the reproductive axis.
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Affiliation(s)
- Vincent Prevot
- Inserm, Jean-Pierre Aubert Research Center, U837, Development and Plasticity of the Postnatal Brain, F-59000 Lille, France.
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Differential distribution of erbB receptors in human glioblastoma multiforme: expression of erbB3 in CD133-positive putative cancer stem cells. J Neuropathol Exp Neurol 2010; 69:606-22. [PMID: 20467331 DOI: 10.1097/nen.0b013e3181e00579] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Glioblastomas are the most common primary central nervous system tumors in adults, and they remain resistant to current treatments. erbB1 signaling is frequently altered in glioblastomas, suggesting thaterbB receptor family members may represent targets for molecular therapy. We performed a comprehensive analysis of erbB receptor and ligand expression profiles in a panel of 9 glioblastomas andcompared them to nonneoplastic cerebral tissue containing neocortex and adjacent white matter. Quantitative reverse transcription-polymerase chain reaction and Western blot analysis showed that erbB1signaling and erbB2 receptors exhibited highly variable deregulation profiles in the tumors, with patterns ranging from underexpression to overexpression; in contrast, erbB3 and erbB4 were downregulated. We next performed immunohistochemistry to determinethe distribution patterns of erbB receptors among the main neuralcell types in the tumors with special reference to the putative tumor stem cell population. Results revealed intertumoral and intratumoral heterogeneity in all 4 erbB expression profiles, but each receptor exhibited a distinct distribution pattern among glial fibrillary acidic protein-, Olig2-, NeuN-, and CD133-positive populations. Although erbB1 immunoreactivity was detected in only small subsets of CD133-positive putative tumor stem cells, erbB3 immunoreactivity was prominent in this population, suggesting that erbB3 may represent a new potential therapeutic target.
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Sharif A, Prevot V. ErbB receptor signaling in astrocytes: a mediator of neuron-glia communication in the mature central nervous system. Neurochem Int 2010; 57:344-58. [PMID: 20685225 DOI: 10.1016/j.neuint.2010.05.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Revised: 03/29/2010] [Accepted: 05/18/2010] [Indexed: 10/19/2022]
Abstract
Astrocytes are now recognized as active players in the developing and mature central nervous system. Each astrocyte contacts vascular structures and thousands of synapses within discrete territories. These cells receive a myriad of inputs and generate appropriate responses to regulate the function of brain microdomains. Emerging evidence has implicated receptors of the ErbB tyrosine kinase family in the integration and processing of neuronal inputs by astrocytes: ErbB receptors can be activated by a wide range of neuronal stimuli; they control critical steps of glutamate-glutamine metabolism; and they regulate the biosynthesis and release of various glial-derived neurotrophic factors, gliomediators and gliotransmitters. These key properties of astrocytic ErbB signaling in neuron-glia interactions have significance for the physiology of the mature central nervous system, as exemplified by the central control of reproduction within the hypothalamus, and are also likely to contribute to pathological situations, since both dysregulation of ErbB signaling and glial dysfunction occur in many neurological disorders.
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Affiliation(s)
- Ariane Sharif
- Inserm, Jean-Pierre Aubert Research Center, U837, Development and Plasticity of the postnatal Brain, Lille, France.
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Dobbertin A, Czvitkovich S, Theocharidis U, Garwood J, Andrews MR, Properzi F, Lin R, Fawcett JW, Faissner A. Analysis of combinatorial variability reveals selective accumulation of the fibronectin type III domains B and D of tenascin-C in injured brain. Exp Neurol 2010; 225:60-73. [PMID: 20451518 DOI: 10.1016/j.expneurol.2010.04.019] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2009] [Revised: 04/23/2010] [Accepted: 04/30/2010] [Indexed: 10/19/2022]
Abstract
Tenascin-C (Tnc) is a multimodular extracellular matrix glycoprotein that is markedly upregulated in CNS injuries where it is primarily secreted by reactive astrocytes. Different Tnc isoforms can be generated by the insertion of variable combinations of one to seven (in rats) alternatively spliced distinct fibronectin type III (FnIII) domains to the smallest variant. Each spliced FnIII repeat mediates specific actions on neurite outgrowth, neuron migration or adhesion. Hence, different Tnc isoforms might differentially influence CNS repair. We explored the expression pattern of Tnc variants after cortical lesions and after treatment of astrocytes with various cytokines. Using RT-PCR, we observed a strong upregulation of Tnc transcripts containing the spliced FnIII domains B or D in injured tissue at 2-4 days post-lesion (dpl). Looking at specific combinations, we showed a dramatic increase of Tnc isoforms harboring the neurite outgrowth-promoting BD repeat with both the B and D domains being adjacent to each other. Isoforms containing only the axon growth-stimulating spliced domain D were also dramatically enhanced after injury. Injury-induced increase of Tnc proteins comprising the domain D was confirmed by Western Blotting and immunostaining of cortical lesions. In contrast, the FnIII modules C and AD1 were weakly modulated after injury. The growth cone repulsive A1A2A4 domains were poorly expressed in normal and injured tissue but the smallest isoform, which is also repellant, was highly expressed after injury. Expression of the shortest Tnc isoform and of variants containing B, D or BD, was strongly upregulated in cultured astrocytes after TGFbeta1 treatment, suggesting that TGFbeta1 could mediate, at least in part, the injury-induced upregulation of these isoforms. We identified complex injury-induced differential regulations of Tnc isoforms that may well influence axonal regeneration and repair processes in the damaged CNS.
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Affiliation(s)
- Alexandre Dobbertin
- Department of Cell Morphology and Molecular Neurobiology, Ruhr University of Bochum, 44780 Bochum, Germany
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Patru C, Romao L, Varlet P, Coulombel L, Raponi E, Cadusseau J, Renault-Mihara F, Thirant C, Leonard N, Berhneim A, Mihalescu-Maingot M, Haiech J, Bièche I, Moura-Neto V, Daumas-Duport C, Junier MP, Chneiweiss H. CD133, CD15/SSEA-1, CD34 or side populations do not resume tumor-initiating properties of long-term cultured cancer stem cells from human malignant glio-neuronal tumors. BMC Cancer 2010; 10:66. [PMID: 20181261 PMCID: PMC2841664 DOI: 10.1186/1471-2407-10-66] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2009] [Accepted: 02/24/2010] [Indexed: 11/15/2022] Open
Abstract
Background Tumor initiating cells (TICs) provide a new paradigm for developing original therapeutic strategies. Methods We screened for TICs in 47 human adult brain malignant tumors. Cells forming floating spheres in culture, and endowed with all of the features expected from tumor cells with stem-like properties were obtained from glioblastomas, medulloblastoma but not oligodendrogliomas. Results A long-term self-renewal capacity was particularly observed for cells of malignant glio-neuronal tumors (MGNTs). Cell sorting, karyotyping and proteomic analysis demonstrated cell stability throughout prolonged passages. Xenografts of fewer than 500 cells in Nude mouse brains induced a progressively growing tumor. CD133, CD15/LeX/Ssea-1, CD34 expressions, or exclusion of Hoechst dye occurred in subsets of cells forming spheres, but was not predictive of their capacity to form secondary spheres or tumors, or to resist high doses of temozolomide. Conclusions Our results further highlight the specificity of a subset of high-grade gliomas, MGNT. TICs derived from these tumors represent a new tool to screen for innovative therapies.
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Affiliation(s)
- Cristina Patru
- Glial Plasticity lab, Inserm UMR 894, University Paris Descartes, Paris, France
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36
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Dufour C, Cadusseau J, Varlet P, Surena AL, de Faria GP, Dias-Morais A, Auger N, Léonard N, Daudigeos E, Dantas-Barbosa C, Grill J, Lazar V, Dessen P, Vassal G, Prevot V, Sharif A, Chneiweiss H, Junier MP. Astrocytes reverted to a neural progenitor-like state with transforming growth factor alpha are sensitized to cancerous transformation. Stem Cells 2010; 27:2373-82. [PMID: 19544474 DOI: 10.1002/stem.155] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Gliomas, the most frequent primitive central nervous system tumors, have been suggested to originate from astrocytes or from neural progenitors/stem cells. However, the precise identity of the cells at the origin of gliomas remains a matter of debate because no pre-neoplastic state has been yet identified. Transforming growth factor (TGF)-alpha, an epidermal growth factor family member, is frequently overexpressed in the early stages of glioma progression. We previously demonstrated that prolonged exposure of astrocytes to TGF-alpha is sufficient to trigger their reversion to a neural progenitor-like state. To determine whether TGF-alpha dedifferentiating effects are associated with cancerous transforming effects, we grafted intracerebrally dedifferentiated astrocytes. We show that these cells had the same cytogenomic profile as astrocytes, survived in vivo, and did not give birth to tumors. When astrocytes dedifferentiated with TGF-alpha were submitted to oncogenic stress using gamma irradiation, they acquired cancerous properties: they were immortalized, showed cytogenomic abnormalities, and formed high-grade glioma-like tumors after brain grafting. In contrast, irradiation did not modify the lifespan of astrocytes cultivated in serum-free medium. Addition of TGF-alpha after irradiation did not promote their transformation but decreased their lifespan. These results demonstrate that reversion of mature astrocytes to an embryonic state without genomic manipulation is sufficient to sensitize them to oncogenic stress.
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Affiliation(s)
- Christelle Dufour
- Inserm UMR894, Team Glial Plasticity, University Paris, Descartes, France
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Sawada N, Liao JK. Targeting eNOS and beyond: emerging heterogeneity of the role of endothelial Rho proteins in stroke protection. Expert Rev Neurother 2009; 9:1171-86. [PMID: 19673606 DOI: 10.1586/ern.09.70] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Currently available modalities for the treatment of acute ischemic stroke are aimed at preserving or augmenting cerebral blood flow. Experimental evidence suggests that statins, which show 25-30% reduction of stroke incidence in clinical trials, confer stroke protection by upregulation of eNOS and increasing cerebral blood flow. The upregulation of eNOS by statins is mediated by inhibition of small GTP-binding protein RhoA. Our recent study uncovered a unique role for a Rho-family member Rac1 in stroke protection. Rac1 in endothelium does not affect cerebral blood flow. Instead, inhibition of endothelial Rac1 leads to broad upregulation of the genes relevant to neurovascular protection. Intriguingly, inhibition of endothelial Rac1 enhances neuronal cell survival through endothelium-derived neurotrophic factors, including artemin. This review discusses the emerging therapeutic opportunities to target neurovascular signaling beyond the BBB, with special emphasis on the novel role of endothelial Rac1 in stroke protection.
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Affiliation(s)
- Naoki Sawada
- Cardiovascular Institute, Beth Israel Deaconess Medical Center, Center for Life Sciences, Boston, MA 02115, USA.
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38
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McCullar JS, Oesterle EC. Cellular targets of estrogen signaling in regeneration of inner ear sensory epithelia. Hear Res 2009; 252:61-70. [PMID: 19450430 PMCID: PMC2975607 DOI: 10.1016/j.heares.2009.01.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2008] [Revised: 01/16/2009] [Accepted: 01/22/2009] [Indexed: 01/19/2023]
Abstract
Estrogen signaling in auditory and vestibular sensory epithelia is a newly emerging focus propelled by the role of estrogen signaling in many other proliferative systems. Understanding the pathways with which estrogen interacts can provide a means to identify how estrogen may modulate proliferative signaling in inner ear sensory epithelia. Reviewed herein are two signaling families, EGF and TGFbeta. Both pathways are involved in regulating proliferation of supporting cells in mature vestibular sensory epithelia and have well characterized interactions with estrogen signaling in other systems. It is becoming increasingly clear that elucidating the complexity of signaling in regeneration will be necessary for development of therapeutics that can initiate regeneration and prevent progression to a pathogenic state.
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Affiliation(s)
- Jennifer S. McCullar
- Virginia Merrill Bloedel Hearing Research Center, Department of Otolaryngology-Head and Neck Surgery, University of Washington, CHDD CD176, P.O. Box 357923, Seattle, WA 98195, USA
| | - Elizabeth C. Oesterle
- Virginia Merrill Bloedel Hearing Research Center, Department of Otolaryngology-Head and Neck Surgery, University of Washington, CHDD CD176, P.O. Box 357923, Seattle, WA 98195, USA
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Brain injury expands the numbers of neural stem cells and progenitors in the SVZ by enhancing their responsiveness to EGF. ASN Neuro 2009; 1:AN20090002. [PMID: 19570028 PMCID: PMC2695583 DOI: 10.1042/an20090002] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
There is an increase in the numbers of neural precursors in the SVZ (subventricular zone) after moderate ischaemic injuries, but the extent of stem cell expansion and the resultant cell regeneration is modest. Therefore our studies have focused on understanding the signals that regulate these processes towards achieving a more robust amplification of the stem/progenitor cell pool. The goal of the present study was to evaluate the role of the EGFR [EGF (epidermal growth factor) receptor] in the regenerative response of the neonatal SVZ to hypoxic/ischaemic injury. We show that injury recruits quiescent cells in the SVZ to proliferate, that they divide more rapidly and that there is increased EGFR expression on both putative stem cells and progenitors. With the amplification of the precursors in the SVZ after injury there is enhanced sensitivity to EGF, but not to FGF (fibroblast growth factor)-2. EGF-dependent SVZ precursor expansion, as measured using the neurosphere assay, is lost when the EGFR is pharmacologically inhibited, and forced expression of a constitutively active EGFR is sufficient to recapitulate the exaggerated proliferation of the neural stem/progenitors that is induced by hypoxic/ischaemic brain injury. Cumulatively, our results reveal that increased EGFR signalling precedes that increase in the abundance of the putative neural stem cells and our studies implicate the EGFR as a key regulator of the expansion of SVZ precursors in response to brain injury. Thus modulating EGFR signalling represents a potential target for therapies to enhance brain repair from endogenous neural precursors following hypoxic/ischaemic and other brain injuries.
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40
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Zehr JL, Nichols LR, Schulz KM, Sisk CL. Adolescent development of neuron structure in dentate gyrus granule cells of male Syrian hamsters. Dev Neurobiol 2009; 68:1517-26. [PMID: 18792070 DOI: 10.1002/dneu.20675] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Hippocampal function, including spatial cognition and stress responses, matures during adolescence. In addition, hippocampal neuron structure is modified by gonadal steroid hormones, which increase dramatically at this time. This study investigated pubertal changes in dendritic complexity of dentate gyrus neurons. Dendrites, spines, and cell bodies of Golgi-impregnated neurons from the granule cell layer were traced in pre-, mid-, and late-pubertal male Syrian hamsters (21, 35, and 49 days of age). Sholl analysis determined the number of intersections and total dendritic length contained in concentric spheres set at 25-microm increments from the soma. Spine densities were quantified separately in proximal and distal segments of a subset of neurons used for the Sholl analysis. We found that the structure of neurons in the lower, but not upper, blade of the dentate gyrus changed during adolescence. The lower, infrapyramidal blade showed pruning of dendrites close to the cell body and increases in distal dendritic spine densities across adolescence. These data demonstrate that dentate gyrus neurons undergo substantial structural remodeling during adolescence and that patterns of maturation are region specific. Furthermore, these changes in dendrite structure, which alter the electrophysiological properties of granule cells, are likely related to the adolescent development of hippocampal-dependent cognitive functions such as learning and memory, as well as hippocampus-mediated stress responsivity.
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Affiliation(s)
- Julia L Zehr
- Neuroscience Program, Michigan State University, East Lansing, Michigan 48824, USA.
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41
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Abstract
Astrocytes in the CNS respond to tissue damage by becoming reactive. They migrate, undergo hypertrophy, and form a glial scar that inhibits axon regeneration. Therefore, limiting astrocytic responses represents a potential therapeutic strategy to improve functional recovery. It was recently shown that the epidermal growth factor (EGF) receptor is upregulated in astrocytes after injury and promotes their transformation into reactive astrocytes. Furthermore, EGF receptor inhibitors were shown to enhance axon regeneration in the injured optic nerve and promote recovery after spinal cord injury. However, the signaling pathways involved were not elucidated. Here we show that in cultures of adult spinal cord astrocytes EGF activates the mTOR pathway, a key regulator of astrocyte physiology. This occurs through Akt-mediated phosphorylation of the GTPase-activating protein Tuberin, which inhibits Tuberin's ability to inactivate the small GTPase Rheb. Indeed, we found that Rheb is required for EGF-dependent mTOR activation in spinal cord astrocytes, whereas the Ras-MAP kinase pathway does not appear to be involved. Moreover, astrocyte growth and EGF-dependent chemoattraction were inhibited by the mTOR-selective drug rapamycin. We also detected elevated levels of activated EGF receptor and mTOR signaling in reactive astrocytes in vivo in an ischemic model of spinal cord injury. Furthermore, increased Rheb expression likely contributes to mTOR activation in the injured spinal cord. Interestingly, injured rats treated with rapamycin showed reduced signs of reactive gliosis, suggesting that rapamycin could be used to harness astrocytic responses in the damaged nervous system to promote an environment more permissive to axon regeneration.
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Sawada N, Kim HH, Moskowitz MA, Liao JK. Rac1 is a critical mediator of endothelium-derived neurotrophic activity. Sci Signal 2009; 2:ra10. [PMID: 19278959 PMCID: PMC2668716 DOI: 10.1126/scisignal.2000162] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The therapeutic potential of neurotrophic factors has been hampered by their inability to achieve adequate tissue penetration. Brain blood vessels, however, could be an alternative target for neurosalvage therapies by virtue of their close proximity to neurons. Here we show that hemizygous deletion of Rac1 in mouse endothelial cells (ECs) attenuates brain injury and edema after focal cerebral ischemia. Microarray analysis of Rac1(+/-) ECs revealed enrichment of stress response genes, basement membrane components, and neurotrophic factors that could affect neuronal survival. Consistent with these expression profiles, endothelial Rac1 hemizygosity enhanced antioxidative and endothelial barrier capacities and potentiated paracrine neuroprotective activities through the up-regulation of the neurotrophic factor, artemin. Endothelial Rac1, therefore, could be an important therapeutic target for promoting endothelial barrier integrity and neurotrophic activity.
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Affiliation(s)
- Naoki Sawada
- Vascular Medicine Research, Brigham and Women's Hospital, 65 Landsdowne Street, Room 275, Cambridge, MA 02139, USA
| | - Hyung-Hwan Kim
- Vascular Medicine Research, Brigham and Women's Hospital, 65 Landsdowne Street, Room 275, Cambridge, MA 02139, USA
| | - Michael A. Moskowitz
- Stroke and Neurovascular Regulation Laboratory, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | - James K. Liao
- Vascular Medicine Research, Brigham and Women's Hospital, 65 Landsdowne Street, Room 275, Cambridge, MA 02139, USA
- To whom correspondence should be addressed. E-mail:
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Sharif A, Duhem-Tonnelle V, Allet C, Baroncini M, Loyens A, Kerr-Conte J, Collier F, Blond S, Ojeda SR, Junier MP, Prevot V. Differential erbB signaling in astrocytes from the cerebral cortex and the hypothalamus of the human brain. Glia 2009; 57:362-79. [DOI: 10.1002/glia.20762] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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44
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Gilbert J, Davis FC. Behavioral effects of systemic transforming growth factor-alpha in Syrian hamsters. Behav Brain Res 2008; 198:440-8. [PMID: 19110003 DOI: 10.1016/j.bbr.2008.11.046] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2008] [Revised: 11/14/2008] [Accepted: 11/20/2008] [Indexed: 12/20/2022]
Abstract
The growth factor, transforming growth factor-alpha (TGF-alpha) is strongly expressed in the hypothalamic circadian pacemaker, the suprachiasmatic nucleus (SCN). TGF-alpha is one of several SCN peptides recently suggested to function as a circadian output signal for the regulation of locomotor activity rhythms in nocturnal rodents. When infused in the brain, TGF-alpha suppresses activity. TGF-alpha suppresses other behaviors as well including feeding, resulting in weight loss. Elevated TGF-alpha is correlated with some cancers, and it is possible the TGF-alpha and its receptor, the epidermal growth factor receptor (EGFR), mediate fatigue and weight loss associated with cancer. If true for cancers outside of the brain, then systemic TGF-alpha should also affect behavior. We tested this hypothesis in hamsters with intraperitoneal injections or week-long subcutaneous infusions of TGF-alpha. Both treatments suppressed activity and infusions caused reduced food consumption and weight loss. To identify areas of the brain that might mediate these effects of systemic TGF-alpha, we used immunohistochemistry to localize cells with an activated MAP kinase signaling pathway (phosphorylated ERK1). Cells were activated in two hypothalamic areas, the paraventricular nucleus and a narrow region surrounding the third ventricle. These sites could not only be targets of TGF-alpha produced in the SCN but could also mediate effects of elevated TGF-alpha from tumors both within and outside the central nervous system.
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Affiliation(s)
- Jenifer Gilbert
- Department of Biology, Northeastern University, Boston, MA 02115, United States
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45
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Maklad A, Nicolai JR, Bichsel KJ, Evenson JE, Lee TC, Threadgill DW, Hansen LA. The EGFR is required for proper innervation to the skin. J Invest Dermatol 2008; 129:690-8. [PMID: 18830272 DOI: 10.1038/jid.2008.281] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
EGFR family members are essential for proper peripheral nervous system development. A role for EGFR itself in peripheral nervous system development in vivo, however, has not been reported. We investigated whether EGFR is required for cutaneous innervation using Egfr null and skin-targeted Egfr mutant mice. Neuronal markers; including PGP9.5, GAP-43, acetylated tubulin, and neurofilaments; revealed that Egfr null dorsal skin was hyperinnervated with a disorganized pattern of innervation. In addition, receptor subtypes such as lanceolate endings were disorganized and immature. To determine whether the hyperinnervation phenotype resulted from a target-derived effect of loss of EGFR, mice lacking EGFR expression in the cutaneous epithelium were examined. These mice retained other aspects of the cutaneous Egfr null phenotype but exhibited normal innervation. The sensory deficits in Egfr null dorsal skin were not associated with any abnormality in the morphology or density of dorsal root ganglion (DRG) neurons or Schwann cells. However, explant and dissociated cell cultures of DRG revealed more extensive branching in Egfr null cultures. These data demonstrate that EGFR is required for proper cutaneous innervation during development and suggest that it limits axonal outgrowth and branching in a DRG-autonomous manner.
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Affiliation(s)
- Adel Maklad
- Department of Biomedical Sciences, Creighton University School of Medicine, Omaha, Nebraska 68178, USA
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46
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Surena AL, de Faria GP, Studler JM, Peiretti F, Pidoux M, Camonis J, Chneiweiss H, Formstecher E, Junier MP. DLG1/SAP97 modulates transforming growth factor alpha bioavailability. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2008; 1793:264-72. [PMID: 18930083 DOI: 10.1016/j.bbamcr.2008.09.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2008] [Revised: 08/06/2008] [Accepted: 09/11/2008] [Indexed: 11/27/2022]
Abstract
TGFalpha and its receptor EGFR participate in the development of a wide range of tumors including gliomas, the main adult primary brain tumors. TGFalpha soluble form results from the cleavage by the metalloprotease TACE/ADAM17 of the extracellular part of its transmembrane precursor, pro-TGFalpha. To gain insights into the mechanisms underlying TGFalpha bioavailability, a yeast two-hybrid screen was performed to identify proteins interacting with pro-TGFalpha intracellular domain (ICD). DLG1/SAP97 (Discs Large Gene 1 or Synapse Associated Protein 97) was found to interact with both pro-TGFalpha and TACE ICDs through distinct PDZ domains. An in vivo pro-TGFalpha-DLG1-TACE complex was detected in U251 glioma cells and in gliomas-derived tumor initiating cells. Interaction between DLG1 and TACE diminished in response to stimulations promoting pro-TGFalpha shedding. Manipulation of DLG1 levels revealed dual actions of DLG1 on pro-TGFalpha shedding, favoring approximation of pro-TGFalpha and TACE, while limiting TACE full shedding activity. These results show that DLG1 participates in the control of TGFalpha bioavailability through its dynamic interaction with the growth factor precursor and TACE.
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47
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White RE, Yin FQ, Jakeman LB. TGF-alpha increases astrocyte invasion and promotes axonal growth into the lesion following spinal cord injury in mice. Exp Neurol 2008; 214:10-24. [PMID: 18647603 DOI: 10.1016/j.expneurol.2008.06.012] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2008] [Revised: 06/02/2008] [Accepted: 06/17/2008] [Indexed: 11/15/2022]
Abstract
Astrocytes respond to environmental cues and play a multifaceted role in the response to trauma in the central nervous system. As the most prevalent contributors to the glial scar, astrocytes are targeted as barriers to regeneration. However, there is also strong evidence that astrocytes are vital for neuroprotection and metabolic support after injury. In addition, consistent with their role during development, astrocytes may be capable of supporting the growth of injured axons. Therefore, we hypothesized that with appropriate stimulation, the reparative functions of endogenous astrocytes could be harnessed to promote axon growth and recovery after spinal cord injury. Transforming growth factor-alpha (TGF-alpha) is a mitogenic growth factor that is active on astrocytes and is poised to contribute to such a strategy. Recombinant TGF-alpha was administered intrathecally to adult C57BL/6 mice for two weeks following a moderate mid-thoracic spinal cord contusion. By three weeks post-injury, TGF-alpha infusion had not affected locomotor recovery, but promoted extensive axon growth and altered the composition of the lesion site. The center of the lesion in the treated mice contained greater numbers of new cells and increased astrocyte invasion. Despite the expression of inhibitory proteoglycans, there was a marked increase in axons expressing neurofilament and GAP-43 immunoreactivity, and the new axons were closely associated with increased laminin expression within and beyond the astrocyte matrix. The results demonstrate that astrocytes are dynamic players in the response to spinal cord injury, and the growth-supportive role of these cells can be enhanced by TGF-alpha infusion.
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Affiliation(s)
- Robin E White
- The Ohio State University, Neuroscience Graduate Studies Program, OH, USA
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48
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Schittenhelm J, Mittelbronn M, Nguyen TD, Meyermann R, Beschorner R. WT1 expression distinguishes astrocytic tumor cells from normal and reactive astrocytes. Brain Pathol 2008; 18:344-53. [PMID: 18371184 DOI: 10.1111/j.1750-3639.2008.00127.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Particularly in small brain biopsies, it might be difficult to distinguish reactive astrogliosis from low-grade or infiltration zones of high-grade astrocytomas. So far no immunohistochemical marker allows a reliable distinction. Recently, the over-expression of Wilms' tumor gene product WT1 was reported in astrocytic tumor cells. However, no sufficient data on WT1 expression in normal or reactive astrocytes are available. Therefore, we investigated WT1 expression in paraffin-embedded brain sections from 28 controls, 48 cases with astrogliosis of various etiology and 219 astrocytomas [World Health Organization (WHO) grades I-IV] by immunohistochemistry. In normal brains and in astrogliosis, expression of WT1 was restricted to endothelial cells. In astrocytomas, WT1-positive tumor cells were found in pilocytic astrocytomas (66.7% of cases), diffuse astrocytomas (52.7%) WHO grade II (52.7%), anaplastic astrocytomas (83.4%) and glioblastomas (98.1%). Overall, the majority of all astrocytic neoplasms (84.5%) expressed WT1. Establishing a cut-off value of 0% immunoreactive tumor cells served to recognize neoplastic astrocytes with 100% specificity and 68% sensitivity and was associated with positive and negative predictive values of 1 and 0.68, respectively. Therefore, WT1 expression in astrocytes indicates a neoplastic origin and might represent an important diagnostic tool to differentiate reactive from neoplastic astrocytes by immunohistochemistry.
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Affiliation(s)
- Jens Schittenhelm
- Institute of Brain Research, University Hospital of Tuebingen, Tuebingen, Germany.
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49
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Ghashghaei HT, Weimer JM, Schmid RS, Yokota Y, McCarthy KD, Popko B, Anton ES. Reinduction of ErbB2 in astrocytes promotes radial glial progenitor identity in adult cerebral cortex. Genes Dev 2008; 21:3258-71. [PMID: 18079173 DOI: 10.1101/gad.1580407] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Radial glial cells play a critical role in the construction of mammalian brain by functioning as a source of new neurons and by providing a scaffold for radial migration of new neurons to their target locations. Radial glia transform into astrocytes at the end of embryonic development. Strategies to promote functional recovery in the injured adult brain depend on the generation of new neurons and the appropriate guidance of these neurons to where they are needed, two critical functions of radial glia. Thus, the competence to regain radial glial identity in the adult brain is of significance for the ability to promote functional repair via neurogenesis and targeted neuronal migration in the mature brain. Here we show that the in vivo induction of the tyrosine kinase receptor, ErbB2, in mature astrocytes enables a subset of them to regain radial glial identity in the mature cerebral cortex. These new radial glial progenitors are capable of giving rise to new neurons and can support neuronal migration. These studies indicate that ErbB2 signaling critically modulates the functional state of radial glia, and induction of ErbB2 in distinct adult astrocytes can promote radial glial identity in the mature cerebral cortex.
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Affiliation(s)
- H T Ghashghaei
- University of North Carolina Neuroscience Center and the Department of Cell and Molecular Physiology, The University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599, USA
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50
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Lindley J, Deurveilher S, Rusak B, Semba K. Transforming growth factor-α and glial fibrillary acidic protein in the hamster circadian system: Daily profile and cellular localization. Brain Res 2008; 1197:94-105. [DOI: 10.1016/j.brainres.2007.12.053] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2007] [Revised: 12/09/2007] [Accepted: 12/17/2007] [Indexed: 10/22/2022]
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