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Bhore N, Wang BJ, Wu PF, Lee YL, Chen YW, Hsu WM, Lee H, Huang YS, Yang DI, Liao YF. Dual-Specificity Phosphatase 15 (DUSP15) Modulates Notch Signaling by Enhancing the Stability of Notch Protein. Mol Neurobiol 2021; 58:2204-2214. [PMID: 33417224 DOI: 10.1007/s12035-020-02254-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 12/08/2020] [Indexed: 11/27/2022]
Abstract
Dual-specificity phosphatases (DUSPs) comprise a unique group of enzymes that dephosphorylate signaling proteins at both phospho-serine/threonine and phospho-tyrosine residues. Since Notch signaling is an essential pathway for neuronal cell fate determination and development that is also upregulated in Alzheimer's disease tissues, we sought to explore whether and how DUSPs may impact Notch processing. Our results show that overexpression of DUSP15 concomitantly and dose-dependently increased the steady-state levels of recombinant Notch (extracellular domain-truncated Notch, NotchΔE) protein and its cleaved product, Notch intracellular domain (NICD). The overall ratio of NotchΔE to NICD was unchanged by overexpression of DUSP15, suggesting that the effect is independent of γ-secretase. Interestingly, overexpression of DUSP15 also dose-dependently increased phosphorylated ERK1/2. Phosphorylated ERK1/2 is known to be positively correlated with Notch protein level, and we found that DUSP15-mediated regulation of Notch was dependent on ERK1/2 activity. Together, our findings reveal the existence of a previously unidentified DUSP15-ERK1/2-Notch signaling axis, which could potentially play a role in neuronal differentiation and neurological disease.
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Affiliation(s)
- Noopur Bhore
- Laboratory of Molecular Neurobiology, Institute of Cellular and Organismic Biology, Academia Sinica, ICOB 238, 128 Sec. 2 Academia Rd, Taipei, 11529, Taiwan.,Taiwan International Graduate Program in Interdisciplinary Neuroscience, National Yang-Ming University, Academia Sinica, Taipei, Taiwan
| | - Bo-Jeng Wang
- Laboratory of Molecular Neurobiology, Institute of Cellular and Organismic Biology, Academia Sinica, ICOB 238, 128 Sec. 2 Academia Rd, Taipei, 11529, Taiwan
| | - Po-Fan Wu
- Laboratory of Molecular Neurobiology, Institute of Cellular and Organismic Biology, Academia Sinica, ICOB 238, 128 Sec. 2 Academia Rd, Taipei, 11529, Taiwan.,Taiwan International Graduate Program in Interdisciplinary Neuroscience, National Cheng Kung University, Academia Sinica, Taipei, Taiwan
| | - Yen-Lurk Lee
- TIGP in Molecular Medicine, National Yang-Ming University, Academia Sinica, Taipei, Taiwan.,Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Yun-Wen Chen
- Laboratory of Molecular Neurobiology, Institute of Cellular and Organismic Biology, Academia Sinica, ICOB 238, 128 Sec. 2 Academia Rd, Taipei, 11529, Taiwan
| | - Wen-Ming Hsu
- Department of Surgery, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Hsinyu Lee
- Department of Life Science, National Taiwan University, Taipei, Taiwan
| | - Yi-Shuian Huang
- Taiwan International Graduate Program in Interdisciplinary Neuroscience, National Yang-Ming University, Academia Sinica, Taipei, Taiwan.,Taiwan International Graduate Program in Interdisciplinary Neuroscience, National Cheng Kung University, Academia Sinica, Taipei, Taiwan.,TIGP in Molecular Medicine, National Yang-Ming University, Academia Sinica, Taipei, Taiwan.,Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Ding-I Yang
- Taiwan International Graduate Program in Interdisciplinary Neuroscience, National Yang-Ming University, Academia Sinica, Taipei, Taiwan.,Institute of Brain Science, National Yang-Ming University, Taipei, Taiwan
| | - Yung-Feng Liao
- Laboratory of Molecular Neurobiology, Institute of Cellular and Organismic Biology, Academia Sinica, ICOB 238, 128 Sec. 2 Academia Rd, Taipei, 11529, Taiwan. .,Taiwan International Graduate Program in Interdisciplinary Neuroscience, National Yang-Ming University, Academia Sinica, Taipei, Taiwan. .,Taiwan International Graduate Program in Interdisciplinary Neuroscience, National Cheng Kung University, Academia Sinica, Taipei, Taiwan.
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2
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Matías-Guiu J, Matías-Guiu JA, Montero-Escribano P, Barcia JA, Canales-Aguirre AA, Mateos-Diaz JC, Gómez-Pinedo U. Particles Containing Cells as a Strategy to Promote Remyelination in Patients With Multiple Sclerosis. Front Neurol 2020; 11:638. [PMID: 32733364 PMCID: PMC7358567 DOI: 10.3389/fneur.2020.00638] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 05/28/2020] [Indexed: 12/11/2022] Open
Abstract
The repair of demyelinated lesions is a key objective in multiple sclerosis research. Remyelination fundamentally depends on oligodendrocyte progenitor cells (OPC) reaching the lesion; this is influenced by numerous factors including age, disease progression time, inflammatory activity, and the pool of OPCs available, whether they be NG2 cells or cells derived from neural stem cells. Administering OPCs has been proposed as a potential cell therapy; however, these cells can only be administered directly. This article discusses the potential administration of OPCs encapsulated within hydrogel particles composed of biocompatible biomaterials, via the nose-to-brain pathway. We also discuss conditions for the indication of this therapy, and such related issues as the influence on endogenous remyelination, migration of OPCs to demyelinated areas, and the immune response, given the autoimmune nature of multiple sclerosis. Chitosan and derivatives constitute the most promising biomaterial for this purpose, although these issues must be addressed. In conclusion, this line of research may yield an alternative to the remyelinating drugs currently being studied.
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Affiliation(s)
- Jorge Matías-Guiu
- Department of Neurology, Institute of Neurosciences, IdISSC, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Madrid, Spain.,Laboratory of Neurobiology, Institute of Neurosciences, IdISSC, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Madrid, Spain
| | - Jordi A Matías-Guiu
- Department of Neurology, Institute of Neurosciences, IdISSC, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Madrid, Spain
| | - Paloma Montero-Escribano
- Department of Neurology, Institute of Neurosciences, IdISSC, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Madrid, Spain
| | - Juan A Barcia
- Department of Neurosurgery, Institute of Neurosciences, IdISSC, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Madrid, Spain
| | - Alejandro A Canales-Aguirre
- Unidad de Evaluación Preclínica, Unidad de Biotecnología Médica y Farmacéutica, Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de Jalisco, Guadalajara, Mexico
| | - Juan C Mateos-Diaz
- Biotecnología Industrial, Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de 12 Jalisco, CIATEJ, Zapopan, Mexico
| | - Ulises Gómez-Pinedo
- Laboratory of Neurobiology, Institute of Neurosciences, IdISSC, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Madrid, Spain
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3
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Khachanova NV. [What do we know about the pathology of gray matter in multiple sclerosis]. Zh Nevrol Psikhiatr Im S S Korsakova 2018; 118:18-22. [PMID: 30160663 DOI: 10.17116/jnevro201811808218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The emergence of modern methods of immunohistochemistry and further development of MRI has led to a deeper understanding of gray matter (GM) pathology in multiple sclerosis (MS). GM involvement can be extensive including both demyelination (cortical lesions) and neuroaxonal damage. The mechanisms of GM damage in MS remain insufficiently studied. There are two concepts: the lesion of GM is primary and is paralleled by changes in white matter (WM), or secondary, i.e. it is a consequence of the pathological process in WM. More research into GM pathology using the latest MRI techniques will contribute to the understanding of pathological changes in both cortical and subcortical GM.
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Affiliation(s)
- N V Khachanova
- Pirogov Russian National Research Medical University, Moscow, Russia
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4
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Mattugini N, Merl-Pham J, Petrozziello E, Schindler L, Bernhagen J, Hauck SM, Götz M. Influence of white matter injury on gray matter reactive gliosis upon stab wound in the adult murine cerebral cortex. Glia 2018; 66:1644-1662. [PMID: 29573353 DOI: 10.1002/glia.23329] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 02/13/2018] [Accepted: 03/02/2018] [Indexed: 01/01/2023]
Abstract
Traumatic brain injury frequently affects the cerebral cortex, yet little is known about the differential effects that occur if only the gray matter (GM) is damaged or if the injury also involves the white matter (WM). To tackle this important question and directly compare similarities and differences in reactive gliosis, we performed stab wound injury affecting GM and WM (GM+) and one restricted to the GM (GM-) in the adult murine cerebral cortex. First, we examined glial reactivity in the regions affected (WM and GM) and determined the influence of WM injury on reactive gliosis in the GM comparing the same area in the two injury paradigms. In the GM+ injury microglia proliferation is increased in the WM compared with GM, while proliferating astrocytes are more abundant in the GM than in the WM. Interestingly, WM lesion exerted a strong influence on the proliferation of the GM glial cells that was most pronounced at early stages, 3 days post lesion. While astrocyte proliferation was increased, NG2 glia proliferation was decreased in the GM+ compared with GM- lesion condition. Importantly, these differences were not observed when a lesion of the same size affected only the GM. Unbiased proteomic analyses further corroborate our findings in support of a profound difference in GM reactivity when WM is also injured and revealed MIF as a key regulator of NG2 glia proliferation.
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Affiliation(s)
- Nicola Mattugini
- Physiological Genomics, Biomedical center (BMC), Ludwig-Maximilians-University (LMU), Großhaderner Str. 9, Planegg/Martinsried, 82152, Germany.,Institute of Stem Cell Research, Helmholtz Center Munich, Biomedical Center (BMC), Department of Physiological Genomics, Ludwig-Maximilians-University (LMU), Großhaderner Str. 9, Planegg/Martinsried, 82152, Germany.,Graduate School of Systemic Neurosciences Ludwig-Maximilians University (LMU), Großhaderner Str. 2, Planegg/Martinsried, 82152, Germany
| | - Juliane Merl-Pham
- Research Unit Protein Science, Helmholtz Center Munich, Ingolstädter Landstrasse 1, Neuherberg, 85764, Germany
| | - Elisabetta Petrozziello
- Institute for Immunology, Biomedical Center (BMC), Ludwig-Maximilians-University (LMU), Großhadernerstr. 9, Planegg/Martinsried, 82152, Germany
| | - Lisa Schindler
- Vascular Biology, Institute for Stroke and Dementia Research (ISD), Ludwig-Maximilians-University (LMU) Munich, Munich, 81377, Germany
| | - Jürgen Bernhagen
- Vascular Biology, Institute for Stroke and Dementia Research (ISD), Ludwig-Maximilians-University (LMU) Munich, Munich, 81377, Germany.,SyNergy Excellence Cluster, Munich, 81377, Germany
| | - Stefanie M Hauck
- Research Unit Protein Science, Helmholtz Center Munich, Ingolstädter Landstrasse 1, Neuherberg, 85764, Germany
| | - Magdalena Götz
- Physiological Genomics, Biomedical center (BMC), Ludwig-Maximilians-University (LMU), Großhaderner Str. 9, Planegg/Martinsried, 82152, Germany.,Institute of Stem Cell Research, Helmholtz Center Munich, Biomedical Center (BMC), Department of Physiological Genomics, Ludwig-Maximilians-University (LMU), Großhaderner Str. 9, Planegg/Martinsried, 82152, Germany.,SyNergy Excellence Cluster, Munich, 81377, Germany
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5
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Bhore N, Wang BJ, Chen YW, Liao YF. Critical Roles of Dual-Specificity Phosphatases in Neuronal Proteostasis and Neurological Diseases. Int J Mol Sci 2017; 18:ijms18091963. [PMID: 28902166 PMCID: PMC5618612 DOI: 10.3390/ijms18091963] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 09/01/2017] [Accepted: 09/07/2017] [Indexed: 12/31/2022] Open
Abstract
Protein homeostasis or proteostasis is a fundamental cellular property that encompasses the dynamic balancing of processes in the proteostasis network (PN). Such processes include protein synthesis, folding, and degradation in both non-stressed and stressful conditions. The role of the PN in neurodegenerative disease is well-documented, where it is known to respond to changes in protein folding states or toxic gain-of-function protein aggregation. Dual-specificity phosphatases have recently emerged as important participants in maintaining balance within the PN, acting through modulation of cellular signaling pathways that are involved in neurodegeneration. In this review, we will summarize recent findings describing the roles of dual-specificity phosphatases in neurodegeneration and offer perspectives on future therapeutic directions.
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Affiliation(s)
- Noopur Bhore
- Taiwan International Graduate Program in Interdisciplinary Neuroscience, National Yang-Ming University and Academia Sinica, Taipei 11529, Taiwan.
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 11529, Taiwan.
| | - Bo-Jeng Wang
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 11529, Taiwan.
| | - Yun-Wen Chen
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 11529, Taiwan.
| | - Yung-Feng Liao
- Taiwan International Graduate Program in Interdisciplinary Neuroscience, National Yang-Ming University and Academia Sinica, Taipei 11529, Taiwan.
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 11529, Taiwan.
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6
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Qu G, Shi H, Wang B, Li S, Zhang A, Gan W. Alterations in the long non‑coding RNA transcriptome in mesangial cells treated with aldosterone in vitro. Mol Med Rep 2017; 16:6004-6012. [PMID: 28849035 PMCID: PMC5865792 DOI: 10.3892/mmr.2017.7313] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 06/23/2017] [Indexed: 12/14/2022] Open
Abstract
Clinical and experimental reports indicate that aldosterone (ALD) contributes to the progression of renal failure independent of its hemodynamic effects. However, the mechanisms remain to be completely elucidated. The aim of the present study was to investigate the alterations of long non-coding RNA (lncRNA) in mesangial cells (MCs) treated with ALD. The present study used MCs treated with 10−6 M ALD as experimental cells. Microarray techniques performed by Agilent Technologies were used to identify the profiles of differentially expressed lncRNAs between the ALD group and the control group. Pathway and gene ontology analysis were applied to determine the roles of the differentially expressed lncRNAs. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) was used to quantify the differentially expressed lncRNAs. A total of 8,459 lncRNA and 13,214 mRNAs with differential expression between MCs treated with and without ALD were identified. The expression of lncRNAs was confirmed by RT-qPCR and the results were consistent with the lncRNA array. The biological functions of lncRNAs are associated with responding to external stimuli, positive regulation of biological and apoptotic processes, cell division, mitosis and nuclear division. The pathways include cell cycle and peroxisome proliferator-activated receptor signaling pathways. The present study revealed distinct sets of lncRNA expressed in MCs treated with ALD, suggesting that this class of transcripts may be involved in the pathogenesis of chronic kidney diseases.
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Affiliation(s)
- Gaoting Qu
- Department of Pediatric Nephrology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210003, P.R. China
| | - Huimin Shi
- Department of Pediatric Nephrology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210003, P.R. China
| | - Bin Wang
- Division of Nephrology, Huashan Hospital and Institute of Nephrology, Fudan University, Shanghai 200040, P.R. China
| | - Shanwen Li
- Department of Pediatric Nephrology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210003, P.R. China
| | - Aiqing Zhang
- Department of Pediatric Nephrology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210003, P.R. China
| | - Weihua Gan
- Department of Pediatric Nephrology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210003, P.R. China
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7
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Tian Y, Wang L, Jia M, Lu T, Ruan Y, Wu Z, Wang L, Liu J, Zhang D. Association of oligodendrocytes differentiation regulator gene DUSP15 with autism. World J Biol Psychiatry 2017; 18:143-150. [PMID: 27223645 DOI: 10.1080/15622975.2016.1178395] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVES Autism is a pervasive neurodevelopmental disorder with high heritability. Genetic factors play crucial roles in the aetiology of autism. Dual specificity phosphatase 15 (DUSP15) has been recognised as a key regulator gene for oligodendrocytes differentiation. A previous study detected one de novo missense variant (p.Thr107Met) with probable deleterious function in exon 6 of DUSP15 among patients with autism. Therefore, we sequenced this mutation in autistic children and performed an association analysis between DUSP15 polymorphisms and autism. METHODS We performed a case-control study between 255 children affected with autism and 427 healthy controls. Four tag-single nucleotide polymorphisms (SNPs) were selected. These SNPs and the previously reported mutation in exon 6 of DUSP15 were genotyped via Sanger sequencing. RESULTS Our results showed that rs3746599 was significantly associated with autism under allelic, additive and dominant models, respectively (χ2 = 9.699, P = 0.0018; χ2 = 16.224, P = 0.001; χ2 = 7.198, P = 0.007). The association remained significant after Bonferroni correction and permutation tests (n = 10,000). We did not detect the missense variant p.Thr107Met reported in previous studies. However, a de novo missense variant of DUSP15 (p.Ala56Thr) with a probable disease-causing effect was detected in one autistic child while absent in healthy controls. CONCLUSIONS Our findings initially suggest that DUSP15 might be a susceptibility gene for autism in Chinese Han population.
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Affiliation(s)
- Ye Tian
- a Institute of Mental Health, Peking University , Beijing , PR China.,b Peking University Sixth Hospital , Beijing , PR China.,c Key Laboratory for Mental Health , Ministry of Health & National Clinical Research Center for Mental Disorders (Peking University) , Beijing , PR China
| | - Lifang Wang
- a Institute of Mental Health, Peking University , Beijing , PR China.,b Peking University Sixth Hospital , Beijing , PR China.,c Key Laboratory for Mental Health , Ministry of Health & National Clinical Research Center for Mental Disorders (Peking University) , Beijing , PR China
| | - Meixiang Jia
- a Institute of Mental Health, Peking University , Beijing , PR China.,b Peking University Sixth Hospital , Beijing , PR China.,c Key Laboratory for Mental Health , Ministry of Health & National Clinical Research Center for Mental Disorders (Peking University) , Beijing , PR China
| | - Tianlan Lu
- a Institute of Mental Health, Peking University , Beijing , PR China.,b Peking University Sixth Hospital , Beijing , PR China.,c Key Laboratory for Mental Health , Ministry of Health & National Clinical Research Center for Mental Disorders (Peking University) , Beijing , PR China
| | - Yanyan Ruan
- a Institute of Mental Health, Peking University , Beijing , PR China.,b Peking University Sixth Hospital , Beijing , PR China.,c Key Laboratory for Mental Health , Ministry of Health & National Clinical Research Center for Mental Disorders (Peking University) , Beijing , PR China
| | - Zhiliu Wu
- a Institute of Mental Health, Peking University , Beijing , PR China.,b Peking University Sixth Hospital , Beijing , PR China.,c Key Laboratory for Mental Health , Ministry of Health & National Clinical Research Center for Mental Disorders (Peking University) , Beijing , PR China
| | - Linyan Wang
- a Institute of Mental Health, Peking University , Beijing , PR China.,b Peking University Sixth Hospital , Beijing , PR China.,c Key Laboratory for Mental Health , Ministry of Health & National Clinical Research Center for Mental Disorders (Peking University) , Beijing , PR China
| | - Jing Liu
- a Institute of Mental Health, Peking University , Beijing , PR China.,b Peking University Sixth Hospital , Beijing , PR China.,c Key Laboratory for Mental Health , Ministry of Health & National Clinical Research Center for Mental Disorders (Peking University) , Beijing , PR China
| | - Dai Zhang
- a Institute of Mental Health, Peking University , Beijing , PR China.,b Peking University Sixth Hospital , Beijing , PR China.,c Key Laboratory for Mental Health , Ministry of Health & National Clinical Research Center for Mental Disorders (Peking University) , Beijing , PR China.,d PKU-IDG/McGovern Institute for Brain Research, Peking University , Beijing , PR China
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8
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Rodríguez-Molina JF, Lopez-Anido C, Ma KH, Zhang C, Olson T, Muth KN, Weider M, Svaren J. Dual specificity phosphatase 15 regulates Erk activation in Schwann cells. J Neurochem 2017; 140:368-382. [PMID: 27891578 PMCID: PMC5250571 DOI: 10.1111/jnc.13911] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 11/15/2016] [Accepted: 11/21/2016] [Indexed: 12/20/2022]
Abstract
Schwann cells and oligodendrocytes are the myelinating cells of the peripheral and central nervous system, respectively. Despite having different myelin components and different transcription factors driving their terminal differentiation there are shared molecular mechanisms between the two. Sox10 is one common transcription factor required for several steps in development of myelinating glia. However, other factors are divergent as Schwann cells need the transcription factor early growth response 2/Krox20 and oligodendrocytes require Myrf. Likewise, some signaling pathways, like the Erk1/2 kinases, are necessary in both cell types for proper myelination. Nonetheless, the molecular mechanisms that control this shared signaling pathway in myelinating cells remain only partially characterized. The hypothesis of this study is that signaling pathways that are similarly regulated in both Schwann cells and oligodendrocytes play central roles in coordinating the differentiation of myelinating glia. To address this hypothesis, we have used genome-wide binding data to identify a relatively small set of genes that are similarly regulated by Sox10 in myelinating glia. We chose one such gene encoding Dual specificity phosphatase 15 (Dusp15) for further analysis in Schwann cell signaling. RNA interference and gene deletion by genome editing in cultured RT4 and primary Schwann cells showed Dusp15 is necessary for full activation of Erk1/2 phosphorylation. In addition, we show that Dusp15 represses expression of several myelin genes, including myelin basic protein. The data shown here support a mechanism by which early growth response 2 activates myelin genes, but also induces a negative feedback loop through Dusp15 to limit over-expression of myelin genes.
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Affiliation(s)
- José F. Rodríguez-Molina
- Cellular and Molecular Pathology Graduate Program, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Camila Lopez-Anido
- Comparative Biomedical Sciences Graduate Program, University of Wisconsin-Madison, Madison, WI 53705, USA
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Ki H. Ma
- Cellular and Molecular Pathology Graduate Program, University of Wisconsin-Madison, Madison, WI 53705, USA
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Chongyu Zhang
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Tyler Olson
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Katharina N. Muth
- Institut für Biochemie, Emil-Fischer-Zentrum, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Matthias Weider
- Institut für Biochemie, Emil-Fischer-Zentrum, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - John Svaren
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
- Department of Comparative Biosciences, University of Wisconsin-Madison, Madison, WI 53705, USA
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9
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Bourgonje AM, Verrijp K, Schepens JTG, Navis AC, Piepers JAF, Palmen CBC, van den Eijnden M, Hooft van Huijsduijnen R, Wesseling P, Leenders WPJ, Hendriks WJAJ. Comprehensive protein tyrosine phosphatase mRNA profiling identifies new regulators in the progression of glioma. Acta Neuropathol Commun 2016; 4:96. [PMID: 27586084 PMCID: PMC5009684 DOI: 10.1186/s40478-016-0372-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 08/19/2016] [Indexed: 12/20/2022] Open
Abstract
The infiltrative behavior of diffuse gliomas severely reduces therapeutic potential of surgical resection and radiotherapy, and urges for the identification of new drug-targets affecting glioma growth and migration. To address the potential role of protein tyrosine phosphatases (PTPs), we performed mRNA expression profiling for 91 of the 109 known human PTP genes on a series of clinical diffuse glioma samples of different grades and compared our findings with in silico knowledge from REMBRANDT and TCGA databases. Overall PTP family expression levels appeared independent of characteristic genetic aberrations associated with lower grade or high grade gliomas. Notably, seven PTP genes (DUSP26, MTMR4, PTEN, PTPRM, PTPRN2, PTPRT and PTPRZ1) were differentially expressed between grade II-III gliomas and (grade IV) glioblastomas. For DUSP26, PTEN, PTPRM and PTPRT, lower expression levels correlated with poor prognosis, and overexpression of DUSP26 or PTPRT in E98 glioblastoma cells reduced tumorigenicity. Our study represents the first in-depth analysis of PTP family expression in diffuse glioma subtypes and warrants further investigations into PTP-dependent signaling events as new entry points for improved therapy.
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10
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Muth KN, Piefke S, Weider M, Sock E, Hermans-Borgmeyer I, Wegner M, Küspert M. The Dual-specificity phosphatase Dusp15 is regulated by Sox10 and Myrf in Myelinating Oligodendrocytes. Glia 2016; 64:2120-2132. [PMID: 27532821 DOI: 10.1002/glia.23044] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Revised: 07/21/2016] [Accepted: 07/22/2016] [Indexed: 11/10/2022]
Abstract
Differentiation of oligodendrocytes and myelin production in the vertebrate central nervous system require highly concerted changes in gene expression. The transcription factors Sox10 and Myrf are both central to this process and jointly regulate expression of myelin genes. Here we show that Sox10 and Myrf also cooperate in the activation of the gene coding for the dual specificity protein phosphatase Dusp15 (also known as VHY) during this process. Activation is mediated by the Dusp15 promoter, which is also sufficient to drive oligodendroglial gene expression in vivo. It contains both a functional Sox10 and a functional Myrf binding site. Whereas Sox10 binds as a monomer, Myrf binds as a trimer. Available data furthermore indicate that cooperative activation is not a function of facilitated binding, but occurs at a later step of the activation process. shRNA-mediated knockdown of Dusp15 reduced expression of early and late differentiation markers in CG4 and primary oligodendroglial cells, whereas Dusp15 overexpression increased it transiently. This argues that Dusp15 is not only a joint target of Sox10 and Myrf in oligodendrocytes but may also mediate some of their effects during oligodendrocyte differentiation and myelin formation. GLIA 2016;64:2120-2132.
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Affiliation(s)
- Katharina N Muth
- Institut Für Biochemie, Emil-Fischer-Zentrum, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Sandra Piefke
- Institut Für Biochemie, Emil-Fischer-Zentrum, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Matthias Weider
- Institut Für Biochemie, Emil-Fischer-Zentrum, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Elisabeth Sock
- Institut Für Biochemie, Emil-Fischer-Zentrum, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | | | - Michael Wegner
- Institut Für Biochemie, Emil-Fischer-Zentrum, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Melanie Küspert
- Institut Für Biochemie, Emil-Fischer-Zentrum, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.
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11
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Park H, Lee HS, Kim SJ. Virtual Screening with Docking Simulations and Biochemical Evaluation of VHY Phosphatase Inhibitors. Chem Pharm Bull (Tokyo) 2016; 63:807-11. [PMID: 26423037 DOI: 10.1248/cpb.c15-00431] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Although VH1-related member Y (VHY) phosphatase is responsible for the pathogenesis of neuroinflammatory diseases, no small-molecule inhibitor of VHY has been reported so far. Here we first report eight VHY inhibitors identified from molecular docking-based virtual screening and subsequent enzyme inhibition assays. These inhibitors exhibit good biochemical potencies against VHY, with associated IC50 values ranging from 1 to 9 µM. Because all these inhibitors were also screened in silico for having desirable physicochemical properties as a drug candidate, they deserve further investigation by structure-activity relationship studies to develop new medicines for the treatment of neuroinflammatory diseases. The structural features of VHY-inhibitor interactions relevant to the micromolar-level inhibitory activity are addressed in detail.
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Affiliation(s)
- Hwangseo Park
- Department of Bioscience and Biotechnology, Sejong University
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12
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Nunes-Xavier CE, Pulido R. Global RT-PCR and RT-qPCR Analysis of the mRNA Expression of the Human PTPome. Methods Mol Biol 2016; 1447:25-37. [PMID: 27514798 DOI: 10.1007/978-1-4939-3746-2_2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Comprehensive comparative gene expression analysis of the tyrosine phosphatase superfamily members (PTPome) under cell- or tissue-specific growth conditions may help to define their individual and specific role in physiology and disease. Semi-quantitative and quantitative PCR are commonly used methods to analyze and measure gene expression. Here, we describe technical aspects of PTPome mRNA expression analysis by semi-quantitative RT-PCR and quantitative RT-PCR (RT-qPCR). We provide a protocol for each method consisting in reverse transcription followed by PCR using a global platform of specific PTP primers. The chapter includes aspects from primer validation to the setup of the PTPome RT-qPCR platform. Examples are given of PTP-profiling gene expression analysis using a human breast cancer cell line upon long-term or short-term treatment with cell signaling-activation agents.
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Affiliation(s)
- Caroline E Nunes-Xavier
- Centro de Investigación Príncipe Felipe, 46013, Valencia, Spain. .,Department of Tumor Biology, Institute for Cancer Research, Oslo University Hospital Radiumhospitalet, 4950, Nydalen, 0424, Oslo, Norway. .,Biocruces Health Research Institute, Pza Cruces s/n, 48903, Barakaldo, Spain.
| | - Rafael Pulido
- Biocruces Health Research Institute, Pza Cruces s/n, 48903, Barakaldo, Spain. .,IKERBASQUE, Basque Foundation for Science, 48013, Bilbao, Spain.
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13
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Luessi F, Kuhlmann T, Zipp F. Remyelinating strategies in multiple sclerosis. Expert Rev Neurother 2014; 14:1315-34. [DOI: 10.1586/14737175.2014.969241] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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14
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Pedraza CE, Taylor C, Pereira A, Seng M, Tham CS, Izrael M, Webb M. Induction of oligodendrocyte differentiation and in vitro myelination by inhibition of rho-associated kinase. ASN Neuro 2014; 6:6/4/1759091414538134. [PMID: 25289646 PMCID: PMC4189421 DOI: 10.1177/1759091414538134] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
In inflammatory demyelinating diseases such as multiple sclerosis (MS), myelin
degradation results in loss of axonal function and eventual axonal degeneration.
Differentiation of resident oligodendrocyte precursor cells (OPCs) leading to
remyelination of denuded axons occurs regularly in early stages of MS but halts as
the pathology transitions into progressive MS. Pharmacological potentiation of
endogenous OPC maturation and remyelination is now recognized as a promising
therapeutic approach for MS. In this study, we analyzed the effects of modulating the
Rho-A/Rho-associated kinase (ROCK) signaling pathway, by the use of selective
inhibitors of ROCK, on the transformation of OPCs into mature, myelinating
oligodendrocytes. Here we demonstrate, with the use of cellular cultures from rodent
and human origin, that ROCK inhibition in OPCs results in a significant generation of
branches and cell processes in early differentiation stages, followed by accelerated
production of myelin protein as an indication of advanced maturation. Furthermore,
inhibition of ROCK enhanced myelin formation in cocultures of human OPCs and neurons
and remyelination in rat cerebellar tissue explants previously demyelinated with
lysolecithin. Our findings indicate that by direct inhibition of this signaling
molecule, the OPC differentiation program is activated resulting in morphological and
functional cell maturation, myelin formation, and regeneration. Altogether, we show
evidence of modulation of the Rho-A/ROCK signaling pathway as a viable target for the
induction of remyelination in demyelinating pathologies.
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Affiliation(s)
- Carlos E Pedraza
- EMD Serono Research & Development Institute, Inc., Billerica, MA, USA
| | | | - Albertina Pereira
- EMD Serono Research & Development Institute, Inc., Billerica, MA, USA
| | - Michelle Seng
- EMD Serono Research & Development Institute, Inc., Billerica, MA, USA
| | - Chui-Se Tham
- EMD Serono Research & Development Institute, Inc., Billerica, MA, USA
| | | | - Michael Webb
- EMD Serono Research & Development Institute, Inc., Billerica, MA, USA
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15
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Ríos P, Nunes-Xavier CE, Tabernero L, Köhn M, Pulido R. Dual-specificity phosphatases as molecular targets for inhibition in human disease. Antioxid Redox Signal 2014; 20:2251-73. [PMID: 24206177 DOI: 10.1089/ars.2013.5709] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
SIGNIFICANCE The dual-specificity phosphatases (DUSPs) constitute a heterogeneous group of cysteine-based protein tyrosine phosphatases, whose members exert a pivotal role in cell physiology by dephosphorylation of phosphoserine, phosphothreonine, and phosphotyrosine residues from proteins, as well as other non-proteinaceous substrates. RECENT ADVANCES A picture is emerging in which a selected group of DUSP enzymes display overexpression or hyperactivity that is associated with human disease, especially human cancer, making feasible targeted therapy approaches based on their inhibition. A panoply of molecular and functional studies on DUSPs have been performed in the previous years, and drug-discovery efforts are ongoing to develop specific and efficient DUSP enzyme inhibitors. This review summarizes the current status on inhibitory compounds targeting DUSPs that belong to the MAP kinase phosphatases-, small-sized atypical-, and phosphatases of regenerating liver subfamilies, whose inhibition could be beneficial for the prevention or mitigation of human disease. CRITICAL ISSUES Achieving specificity, potency, and bioavailability are the major challenges in the discovery of DUSP inhibitors for the clinics. Clinical validation of compounds or alternative inhibitory strategies of DUSP inhibition has yet to come. FUTURE DIRECTIONS Further work is required to understand the dual role of many DUSPs in human cancer, their function-structure properties, and to identify their physiologic substrates. This will help in the implementation of therapies based on DUSPs inhibition.
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Affiliation(s)
- Pablo Ríos
- 1 Genome Biology Unit, European Molecular Biology Laboratory , Heidelberg, Germany
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16
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Dutta R. Gene expression changes underlying cortical pathology: clues to understanding neurological disability in multiple sclerosis. Mult Scler 2014; 19:1249-54. [PMID: 23996595 DOI: 10.1177/1352458513500554] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system with an unknown etiology. The clinical disease course is variable, with the majority of patients experiencing reversible episodes of neurological disability in the third or fourth decade of life, eventually followed by a state of irreversible progression. Continuous axonal and neuronal loss is thought to be the major cause of this progression. Over the last decade, extensive research has targeted the gray matter and its role in MS pathogenesis. While pathological and imaging studies have begun to reveal important clues about the role of cortical pathology, gene expression studies in MS cortex are still emerging. Microarray-based comparative gene expression profiling provides a snapshot of genes underlying a particular condition and has been performed using brain tissues from patients with progressive MS. In this review, we summarize existing data from gene expression changes in cortical tissues from MS brains and how they may provide clues to the pathogenesis.
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Affiliation(s)
- Ranjan Dutta
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
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17
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Jeong DG, Wei CH, Ku B, Jeon TJ, Chien PN, Kim JK, Park SY, Hwang HS, Ryu SY, Park H, Kim DS, Kim SJ, Ryu SE. The family-wide structure and function of human dual-specificity protein phosphatases. ACTA ACUST UNITED AC 2014; 70:421-35. [PMID: 24531476 DOI: 10.1107/s1399004713029866] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Accepted: 10/31/2013] [Indexed: 11/10/2022]
Abstract
Dual-specificity protein phosphatases (DUSPs), which dephosphorylate both phosphoserine/threonine and phosphotyrosine, play vital roles in immune activation, brain function and cell-growth signalling. A family-wide structural library of human DUSPs was constructed based on experimental structure determination supplemented with homology modelling. The catalytic domain of each individual DUSP has characteristic features in the active site and in surface-charge distribution, indicating substrate-interaction specificity. The active-site loop-to-strand switch occurs in a subtype-specific manner, indicating that the switch process is necessary for characteristic substrate interactions in the corresponding DUSPs. A comprehensive analysis of the activity-inhibition profile and active-site geometry of DUSPs revealed a novel role of the active-pocket structure in the substrate specificity of DUSPs. A structure-based analysis of redox responses indicated that the additional cysteine residues are important for the protection of enzyme activity. The family-wide structures of DUSPs form a basis for the understanding of phosphorylation-mediated signal transduction and the development of therapeutics.
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Affiliation(s)
- Dae Gwin Jeong
- Medical Proteomics Research Center, KRIBB, Daejeon, Republic of Korea
| | - Chun Hua Wei
- Department of Bioengineering, College of Engineering, Hanyang University, Seoul, Republic of Korea
| | - Bonsu Ku
- Medical Proteomics Research Center, KRIBB, Daejeon, Republic of Korea
| | - Tae Jin Jeon
- Department of Bioengineering, College of Engineering, Hanyang University, Seoul, Republic of Korea
| | - Pham Ngoc Chien
- Department of Bioengineering, College of Engineering, Hanyang University, Seoul, Republic of Korea
| | - Jae Kwan Kim
- Department of Industrial Engineering, College of Engineering, Hanyang University, Seoul, Republic of Korea
| | - So Ya Park
- Department of Bioengineering, College of Engineering, Hanyang University, Seoul, Republic of Korea
| | - Hyun Sook Hwang
- Department of Bioengineering, College of Engineering, Hanyang University, Seoul, Republic of Korea
| | - Sun Young Ryu
- Department of Bioengineering, College of Engineering, Hanyang University, Seoul, Republic of Korea
| | - Hwangseo Park
- Department of Bioscience and Biotechnology, Sejong University, Seoul, Republic of Korea
| | - Deok-Soo Kim
- Department of Industrial Engineering, College of Engineering, Hanyang University, Seoul, Republic of Korea
| | - Seung Jun Kim
- Medical Proteomics Research Center, KRIBB, Daejeon, Republic of Korea
| | - Seong Eon Ryu
- Department of Bioengineering, College of Engineering, Hanyang University, Seoul, Republic of Korea
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Fischer MT, Wimmer I, Höftberger R, Gerlach S, Haider L, Zrzavy T, Hametner S, Mahad D, Binder CJ, Krumbholz M, Bauer J, Bradl M, Lassmann H. Disease-specific molecular events in cortical multiple sclerosis lesions. ACTA ACUST UNITED AC 2013; 136:1799-815. [PMID: 23687122 PMCID: PMC3673462 DOI: 10.1093/brain/awt110] [Citation(s) in RCA: 209] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Cortical lesions constitute an important part of multiple sclerosis pathology. Although inflammation appears to play a role in their formation, the mechanisms leading to demyelination and neurodegeneration are poorly understood. We aimed to identify some of these mechanisms by combining gene expression studies with neuropathological analysis. In our study, we showed that the combination of inflammation, plaque-like primary demyelination and neurodegeneration in the cortex is specific for multiple sclerosis and is not seen in other chronic inflammatory diseases mediated by CD8-positive T cells (Rasmussen's encephalitis), B cells (B cell lymphoma) or complex chronic inflammation (tuberculous meningitis, luetic meningitis or chronic purulent meningitis). In addition, we performed genome-wide microarray analysis comparing micro-dissected active cortical multiple sclerosis lesions with those of tuberculous meningitis (inflammatory control), Alzheimer's disease (neurodegenerative control) and with cortices of age-matched controls. More than 80% of the identified multiple sclerosis-specific genes were related to T cell-mediated inflammation, microglia activation, oxidative injury, DNA damage and repair, remyelination and regenerative processes. Finally, we confirmed by immunohistochemistry that oxidative damage in cortical multiple sclerosis lesions is associated with oligodendrocyte and neuronal injury, the latter also affecting axons and dendrites. Our study provides new insights into the complex mechanisms of neurodegeneration and regeneration in the cortex of patients with multiple sclerosis.
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Affiliation(s)
- Marie Therese Fischer
- Department of Neuroimmunology, Centre for Brain Research, Medical University of Vienna, Austria
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19
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Promoting remyelination for the treatment of multiple sclerosis: opportunities and challenges. Neurosci Bull 2013; 29:144-54. [PMID: 23558587 DOI: 10.1007/s12264-013-1317-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2012] [Accepted: 02/06/2013] [Indexed: 01/06/2023] Open
Abstract
Multiple sclerosis (MS) is a chronic and devastating autoimmune demyelinating disease of the central nervous system. With the increased understanding of the pathophysiology of this disease in the past two decades, many disease-modifying therapies that primarily target adaptive immunity have been shown to prevent exacerbations and new lesions in patients with relapsing-remitting MS. However, these therapies only have limited efficacy on the progression of disability. Increasing evidence has pointed to innate immunity, axonal damage and neuronal loss as important contributors to disease progression. Remyelination of denuded axons is considered an effective way to protect neurons from damage and to restore neuronal function. The identification of several key molecules and pathways controlling the differentiation of oligodendrocyte progenitor cells and myelination has yielded clues for the development of drug candidates that directly target remyelination and neuroprotection. The long-term efficacy of this strategy remains to be evaluated in clinical trials. Here, we provide an overview of current and emerging therapeutic concepts, with a focus on the opportunities and challenges for the remyelination approach to the treatment of MS.
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20
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Arora D, Köthe S, van den Eijnden M, Hooft van Huijsduijnen R, Heidel F, Fischer T, Scholl S, Tölle B, Böhmer SA, Lennartsson J, Isken F, Müller-Tidow C, Böhmer FD. Expression of protein-tyrosine phosphatases in Acute Myeloid Leukemia cells: FLT3 ITD sustains high levels of DUSP6 expression. Cell Commun Signal 2012; 10:19. [PMID: 22784513 PMCID: PMC3464674 DOI: 10.1186/1478-811x-10-19] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Accepted: 06/24/2012] [Indexed: 12/25/2022] Open
Abstract
Protein-tyrosine phosphatases (PTPs) are important regulators of cellular signaling and changes in PTP activity can contribute to cell transformation. Little is known about the role of PTPs in Acute Myeloid Leukemia (AML). The aim of this study was therefore to establish a PTP expression profile in AML cells and to explore the possible role of FLT3 ITD (Fms-like tyrosine kinase 3 with internal tandem duplication), an important oncoprotein in AML for PTP gene expression. PTP mRNA expression was analyzed in AML cells from patients and in cell lines using a RT-qPCR platform for detection of transcripts of 92 PTP genes. PTP mRNA expression was also analyzed based on a public microarray data set for AML patients. Highly expressed PTPs in AML belong to all PTP subfamilies. Very abundantly expressed PTP genes include PTPRC, PTPN2, PTPN6, PTPN22, DUSP1, DUSP6, DUSP10, PTP4A1, PTP4A2, PTEN, and ACP1. PTP expression was further correlated with the presence of FLT3 ITD, focusing on a set of highly expressed dual-specificity phosphatases (DUSPs). Elevated expression of DUSP6 in patients harboring FLT3 ITD was detected in this analysis. The mechanism and functional role of FLT3 ITD-mediated upregulation of DUSP6 was then explored using pharmacological inhibitors of FLT3 ITD signal transduction and si/shRNA technology in human and murine cell lines. High DUSP6 expression was causally associated with the presence of FLT3 ITD and dependent on FLT3 ITD kinase activity and ERK signaling. DUSP6 depletion moderately increased ERK1/2 activity but attenuated FLT3 ITD-dependent cell proliferation of 32D cells. In conclusion, DUSP6 may play a contributing role to FLT3 ITD-mediated cell transformation.
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Affiliation(s)
- Deepika Arora
- Institute of Molecular Cell Biology, Center for Molecular Biomedicine, Jena University Hospital, Jena, Germany.
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