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Yao Q, Long C, Yi P, Zhang G, Wan W, Rao X, Ying J, Liang W, Hua F. C/EBPβ: A transcription factor associated with the irreversible progression of Alzheimer's disease. CNS Neurosci Ther 2024; 30:e14721. [PMID: 38644578 PMCID: PMC11033503 DOI: 10.1111/cns.14721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 03/20/2024] [Accepted: 03/27/2024] [Indexed: 04/23/2024] Open
Abstract
BACKGROUND Alzheimer's disease (AD) is a neurodegenerative disorder distinguished by a swift cognitive deterioration accompanied by distinctive pathological hallmarks such as extracellular Aβ (β-amyloid) peptides, neuronal neurofibrillary tangles (NFTs), sustained neuroinflammation, and synaptic degeneration. The elevated frequency of AD cases and its proclivity to manifest at a younger age present a pressing challenge in the quest for novel therapeutic interventions. Numerous investigations have substantiated the involvement of C/EBPβ in the progression of AD pathology, thus indicating its potential as a therapeutic target for AD treatment. AIMS Several studies have demonstrated an elevation in the expression level of C/EBPβ among individuals afflicted with AD. Consequently, this review predominantly delves into the association between C/EBPβ expression and the pathological progression of Alzheimer's disease, elucidating its underlying molecular mechanism, and pointing out the possibility that C/EBPβ can be a new therapeutic target for AD. METHODS A systematic literature search was performed across multiple databases, including PubMed, Google Scholar, and so on, utilizing predetermined keywords and MeSH terms, without temporal constraints. The inclusion criteria encompassed diverse study designs, such as experimental, case-control, and cohort studies, restricted to publications in the English language, while conference abstracts and unpublished sources were excluded. RESULTS Overexpression of C/EBPβ exacerbates the pathological features of AD, primarily by promoting neuroinflammation and mediating the transcriptional regulation of key molecular pathways, including δ-secretase, apolipoprotein E4 (APOE4), acidic leucine-rich nuclear phosphoprotein-32A (ANP32A), transient receptor potential channel 1 (TRPC1), and Forkhead BoxO (FOXO). DISCUSSION The correlation between overexpression of C/EBPβ and the pathological development of AD, along with its molecular mechanisms, is evident. Investigating the pathways through which C/EBPβ regulates the development of AD reveals numerous multiple vicious cycle pathways exacerbating the pathological progression of the disease. Furthermore, the exacerbation of pathological progression due to C/EBPβ overexpression and its molecular mechanism is not limited to AD but also extends to other neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS), Parkinson's disease (PD), and multiple sclerosis (MS). CONCLUSION The overexpression of C/EBPβ accelerates the irreversible progression of AD pathophysiology. Additionally, C/EBPβ plays a crucial role in mediating multiple pathways linked to AD pathology, some of which engender vicious cycles, leading to the establishment of feedback mechanisms. To sum up, targeting C/EBPβ could hold promise as a therapeutic strategy not only for AD but also for other degenerative diseases.
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Affiliation(s)
- Qing Yao
- Department of AnesthesiologyThe Second Affiliated Hospital of Nanchang UniversityNanchang CityJiangxi ProvinceChina
- Key Laboratory of Anesthesiology of Jiangxi ProvinceNanchang CityJiangxi ProvinceChina
| | - Chubing Long
- Department of AnesthesiologyThe Second Affiliated Hospital of Nanchang UniversityNanchang CityJiangxi ProvinceChina
- Key Laboratory of Anesthesiology of Jiangxi ProvinceNanchang CityJiangxi ProvinceChina
| | - Pengcheng Yi
- Department of AnesthesiologyThe Second Affiliated Hospital of Nanchang UniversityNanchang CityJiangxi ProvinceChina
- Key Laboratory of Anesthesiology of Jiangxi ProvinceNanchang CityJiangxi ProvinceChina
| | - Guangyong Zhang
- Department of AnesthesiologyThe Second Affiliated Hospital of Nanchang UniversityNanchang CityJiangxi ProvinceChina
- Key Laboratory of Anesthesiology of Jiangxi ProvinceNanchang CityJiangxi ProvinceChina
| | - Wei Wan
- Department of AnesthesiologyThe Second Affiliated Hospital of Nanchang UniversityNanchang CityJiangxi ProvinceChina
- Key Laboratory of Anesthesiology of Jiangxi ProvinceNanchang CityJiangxi ProvinceChina
| | - Xiuqin Rao
- Department of AnesthesiologyThe Second Affiliated Hospital of Nanchang UniversityNanchang CityJiangxi ProvinceChina
- Key Laboratory of Anesthesiology of Jiangxi ProvinceNanchang CityJiangxi ProvinceChina
| | - Jun Ying
- Department of AnesthesiologyThe Second Affiliated Hospital of Nanchang UniversityNanchang CityJiangxi ProvinceChina
- Key Laboratory of Anesthesiology of Jiangxi ProvinceNanchang CityJiangxi ProvinceChina
| | - Weidong Liang
- Department of AnesthesiologyThe First Affiliated Hospital of Gannan Medical UniversityGanzhouJiangxi ProvinceChina
| | - Fuzhou Hua
- Department of AnesthesiologyThe Second Affiliated Hospital of Nanchang UniversityNanchang CityJiangxi ProvinceChina
- Key Laboratory of Anesthesiology of Jiangxi ProvinceNanchang CityJiangxi ProvinceChina
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C/EBPβ Regulates TFAM Expression, Mitochondrial Function and Autophagy in Cellular Models of Parkinson's Disease. Int J Mol Sci 2023; 24:ijms24021459. [PMID: 36674978 PMCID: PMC9865173 DOI: 10.3390/ijms24021459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 12/30/2022] [Accepted: 01/09/2023] [Indexed: 01/14/2023] Open
Abstract
Parkinson's disease (PD) is a neurodegenerative disorder that results from the degeneration of dopaminergic neurons in the substantia nigra pars compacta (SNpc). Since there are only symptomatic treatments available, new cellular and molecular targets involved in the onset and progression of this disease are needed to develop effective treatments. CCAAT/Enhancer Binding Protein β (C/EBPβ) transcription factor levels are altered in patients with a variety of neurodegenerative diseases, suggesting that it may be a good therapeutic target for the treatment of PD. A list of genes involved in PD that can be regulated by C/EBPβ was generated by the combination of genetic and in silico data, the mitochondrial transcription factor A (TFAM) being among them. In this paper, we observed that C/EBPβ overexpression increased TFAM promoter activity. However, downregulation of C/EBPβ in different PD/neuroinflammation cellular models produced an increase in TFAM levels, together with other mitochondrial markers. This led us to propose an accumulation of non-functional mitochondria possibly due to the alteration of their autophagic degradation in the absence of C/EBPβ. Then, we concluded that C/EBPβ is not only involved in harmful processes occurring in PD, such as inflammation, but is also implicated in mitochondrial function and autophagy in PD-like conditions.
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Kalyan M, Tousif AH, Sonali S, Vichitra C, Sunanda T, Praveenraj SS, Ray B, Gorantla VR, Rungratanawanich W, Mahalakshmi AM, Qoronfleh MW, Monaghan TM, Song BJ, Essa MM, Chidambaram SB. Role of Endogenous Lipopolysaccharides in Neurological Disorders. Cells 2022; 11:cells11244038. [PMID: 36552802 PMCID: PMC9777235 DOI: 10.3390/cells11244038] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Revised: 12/02/2022] [Accepted: 12/12/2022] [Indexed: 12/15/2022] Open
Abstract
Lipopolysaccharide (LPS) is a cell-wall immunostimulatory endotoxin component of Gram-negative bacteria. A growing body of evidence reveals that alterations in the bacterial composition of the intestinal microbiota (gut dysbiosis) disrupt host immune homeostasis and the intestinal barrier function. Microbial dysbiosis leads to a proinflammatory milieu and systemic endotoxemia, which contribute to the development of neurodegenerative diseases and metabolic disorders. Two important pathophysiological hallmarks of neurodegenerative diseases (NDDs) are oxidative/nitrative stress and inflammation, which can be initiated by elevated intestinal permeability, with increased abundance of pathobionts. These changes lead to excessive release of LPS and other bacterial products into blood, which in turn induce chronic systemic inflammation, which damages the blood-brain barrier (BBB). An impaired BBB allows the translocation of potentially harmful bacterial products, including LPS, and activated neutrophils/leucocytes into the brain, which results in neuroinflammation and apoptosis. Chronic neuroinflammation causes neuronal damage and synaptic loss, leading to memory impairment. LPS-induced inflammation causes inappropriate activation of microglia, astrocytes, and dendritic cells. Consequently, these alterations negatively affect mitochondrial function and lead to increases in oxidative/nitrative stress and neuronal senescence. These cellular changes in the brain give rise to specific clinical symptoms, such as impairment of locomotor function, muscle weakness, paralysis, learning deficits, and dementia. This review summarizes the contributing role of LPS in the development of neuroinflammation and neuronal cell death in various neurodegenerative diseases.
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Affiliation(s)
- Manjunath Kalyan
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India
- Centre for Experimental Pharmacology and Toxicology, Central Animal Facility, JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India
| | - Ahmed Hediyal Tousif
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India
- Centre for Experimental Pharmacology and Toxicology, Central Animal Facility, JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India
| | - Sharma Sonali
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India
- Centre for Experimental Pharmacology and Toxicology, Central Animal Facility, JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India
| | - Chandrasekaran Vichitra
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India
- Centre for Experimental Pharmacology and Toxicology, Central Animal Facility, JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India
| | - Tuladhar Sunanda
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India
- Centre for Experimental Pharmacology and Toxicology, Central Animal Facility, JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India
| | - Sankar Simla Praveenraj
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India
| | - Bipul Ray
- Section of Molecular Pharmacology and Toxicology, Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, MD 20892, USA
| | - Vasavi Rakesh Gorantla
- Department of Anatomical sciences, School of Medicine, St. George’s University Grenada, West Indies FZ818, Grenada
| | - Wiramon Rungratanawanich
- Section of Molecular Pharmacology and Toxicology, Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, MD 20892, USA
| | - Arehally M. Mahalakshmi
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India
| | - M. Walid Qoronfleh
- Q3CG Research Institute (QRI), Research & Policy Division, 7227 Rachel Drive, Ypsilanti, MI 48917, USA
- 21 Health Street, Consulting Services, 1 Christian Fields, London SW16 3JY, UK
| | - Tanya M. Monaghan
- National Institute for Health Research Nottingham Biomedical Research Centre, University of Nottingham, Nottingham NG7 2UH, UK
- Nottingham Digestive Diseases Centre, School of Medicine, University of Nottingham, Nottingham NG7 2UH, UK
| | - Byoung-Joon Song
- Section of Molecular Pharmacology and Toxicology, Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, MD 20892, USA
- Correspondence: (B.-J.S.); (M.M.E.); (S.B.C.)
| | - Musthafa Mohamed Essa
- Department of Food Science and Nutrition, CAMS, Sultan Qaboos University, Muscat 123, Oman
- Aging and Dementia Research Group, Sultan Qaboos University, Muscat 123, Oman
- Correspondence: (B.-J.S.); (M.M.E.); (S.B.C.)
| | - Saravana Babu Chidambaram
- Department of Pharmacology, JSS College of Pharmacy, JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India
- Centre for Experimental Pharmacology and Toxicology, Central Animal Facility, JSS Academy of Higher Education & Research, Mysuru 570015, Karnataka, India
- Correspondence: (B.-J.S.); (M.M.E.); (S.B.C.)
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Enrich-Bengoa J, Manich G, Valente T, Sanchez-Molina P, Almolda B, Solà C, Saura J, González B, Castellano B, Perálvarez-Marín A. TRPV2: A Key Player in Myelination Disorders of the Central Nervous System. Int J Mol Sci 2022; 23:ijms23073617. [PMID: 35408977 PMCID: PMC8999035 DOI: 10.3390/ijms23073617] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 03/21/2022] [Accepted: 03/22/2022] [Indexed: 01/27/2023] Open
Abstract
Transient potential receptor vanilloid 2 (TRPV2) is widely expressed through the nervous system and specifically found in neuronal subpopulations and some glial cells. TRPV2 is known to be sensitized by methionine oxidation, which results from inflammation. Here we aim to characterize the expression and regulation of TRPV2 in myelination pathologies, such as hypomyelination and demyelination. We validated the interaction between TRPV2 and its putative interactor Opalin, an oligodendrocyte marker, in mixed glial cultures under pro- and anti-inflammatory conditions. Then, we characterized TRPV2 time-course expression in experimental animal models of hypomyelination (jimpy mice) and de-/remyelination (cuprizone intoxication and experimental autoimmune encephalomyelitis (EAE)). TRPV2 showed upregulation associated with remyelination, inflammation in cuprizone and EAE models, and downregulation in hypomyelinated jimpy mice. TRPV2 expression was altered in human samples of multiple sclerosis (MS) patients. Additionally, we analyzed the expression of methionine sulfoxide reductase A (MSRA), an enzyme that reduces oxidated methionines in TRPV2, which we found increased in inflammatory conditions. These results suggest that TRPV2 may be a key player in myelination in accordance with the recapitulation hypothesis, and that it may become an interesting clinical target in the treatment of demyelination disorders.
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Affiliation(s)
- Jennifer Enrich-Bengoa
- Biophysics Unit, Department of Biochemistry and Molecular Biology, School of Medicine, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain;
- Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain; (G.M.); (T.V.); (P.S.-M.); (B.A.); (B.G.); (B.C.)
| | - Gemma Manich
- Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain; (G.M.); (T.V.); (P.S.-M.); (B.A.); (B.G.); (B.C.)
- Medical Histology Unit, Department of Cell Biology, Physiology and Immunology, School of Medicine, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain
| | - Tony Valente
- Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain; (G.M.); (T.V.); (P.S.-M.); (B.A.); (B.G.); (B.C.)
- Medical Histology Unit, Department of Cell Biology, Physiology and Immunology, School of Medicine, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain
- Research Group on Methodology, Methods, Models and Outcomes of Health and Social Sciences (M3O), Experimental Sciences and Methodological Department, Faculty of Health Sciences and Welfare, University of Vic-Central University of Catalonia (UVic-UCC), 08500 Vic, Catalonia, Spain
| | - Paula Sanchez-Molina
- Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain; (G.M.); (T.V.); (P.S.-M.); (B.A.); (B.G.); (B.C.)
- Medical Histology Unit, Department of Cell Biology, Physiology and Immunology, School of Medicine, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain
| | - Beatriz Almolda
- Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain; (G.M.); (T.V.); (P.S.-M.); (B.A.); (B.G.); (B.C.)
- Medical Histology Unit, Department of Cell Biology, Physiology and Immunology, School of Medicine, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain
| | - Carme Solà
- Department of Cerebral Ischemia and Neurodegeneration, Institut D’Investigacions Biomèdiques de Barcelona-Consejo Superior de Investigaciones Científicas (CSIC), Institut D’Investigacions Biomèdiques August-Pi i Sunyer (IDIBAPS), 08036 Barcelona, Catalonia, Spain;
| | - Josep Saura
- Biochemistry and Molecular Biology Unit, School of Medicine, Institut D’Investigacions Biomèdiques August-Pi i Sunyer (IDIBAPS), University of Barcelona, 08036 Barcelona, Catalonia, Spain;
| | - Berta González
- Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain; (G.M.); (T.V.); (P.S.-M.); (B.A.); (B.G.); (B.C.)
- Medical Histology Unit, Department of Cell Biology, Physiology and Immunology, School of Medicine, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain
| | - Bernardo Castellano
- Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain; (G.M.); (T.V.); (P.S.-M.); (B.A.); (B.G.); (B.C.)
- Medical Histology Unit, Department of Cell Biology, Physiology and Immunology, School of Medicine, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain
| | - Alex Perálvarez-Marín
- Biophysics Unit, Department of Biochemistry and Molecular Biology, School of Medicine, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain;
- Institut de Neurociències, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain; (G.M.); (T.V.); (P.S.-M.); (B.A.); (B.G.); (B.C.)
- Correspondence: ; Tel.: +34-93-581-4504
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Yamashita H, Komine O, Fujimori-Tonou N, Yamanaka K. Comprehensive expression analysis with cell-type-specific transcriptome in ALS-linked mutant SOD1 mice: Revisiting the active role of glial cells in disease. Front Cell Neurosci 2022; 16:1045647. [PMID: 36687517 PMCID: PMC9846815 DOI: 10.3389/fncel.2022.1045647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 12/05/2022] [Indexed: 01/06/2023] Open
Abstract
Non-cell autonomous mechanisms are involved in the pathogenesis of amyotrophic lateral sclerosis (ALS), an adult neurodegenerative disease characterized by selective motor neuron loss. While the emerging role of glial cells in ALS has been noted, the detailed cell-type-specific role of glial cells has not been clarified. Here, we examined mRNA expression changes using microarrays of the spinal cords of three distinct lines of mutant superoxide dismutase (SOD) 1 transgenic mice, an established ALS model. Our analysis used a transcriptome database of component cell types in the central nervous system (CNS), as well as SOD1 G93A cell-type transcriptomes. More than half of the differentially expressed genes (DEGs) were highly expressed in microglia, and enrichment analysis of DEGs revealed that immunological reactions were profoundly involved and some transcription factors were upregulated. Our analysis focused on DEGs that are highly expressed in each cell type, as well as chemokines, caspases, and heat shock proteins. Disease-associated microglial genes were upregulated, while homeostatic microglial genes were not, and galectin-3 (Mac2), a known activated microglial marker, was predicted to be ectopically expressed in astrocytes in mutant SOD1 mice. In mutant SOD1 mice, we developed a prediction model for the pathophysiology of different cell types related to TREM2, apolipoprotein E, and lipoproteins. Our analysis offers a viable resource to understand not only the molecular pathologies of each CNS constituent cell type, but also the cellular crosstalk between different cell types under both physiological and pathological conditions in model mice for various neurodegenerative diseases.
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Affiliation(s)
- Hirofumi Yamashita
- Department of Neurology, Japanese Red Cross Wakayama Medical Center, Wakayama, Japan.,Department of Neurology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.,Department of Neuroscience and Pathobiology, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan
| | - Okiru Komine
- Department of Neuroscience and Pathobiology, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan
| | - Noriko Fujimori-Tonou
- Support Unit for Bio-Material Analysis, RRD, RIKEN Center for Brain Science, Wako, Japan
| | - Koji Yamanaka
- Department of Neuroscience and Pathobiology, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan.,Department of Neuroscience and Pathobiology, Nagoya University Graduate School of Medicine, Nagoya University, Nagoya, Japan.,Institute for Glyco-Core Research (iGCORE), Nagoya University, Nagoya, Japan
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Wang R, Zhang S, Yang Z, Zheng Y, Yan F, Tao Z, Fan J, Zhao H, Han Z, Luo Y. Mutant erythropoietin enhances white matter repair via the JAK2/STAT3 and C/EBPβ pathway in middle-aged mice following cerebral ischemia and reperfusion. Exp Neurol 2021; 337:113553. [PMID: 33309747 DOI: 10.1016/j.expneurol.2020.113553] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 11/06/2020] [Accepted: 12/07/2020] [Indexed: 01/20/2023]
Abstract
Previous studies have indicated that EPO maintains the M2 microglia phenotype that contributes to white matter repair after ischemic stroke in young mice (2 months old). However, the underlying mechanisms that regulate microglial polarization are poorly defined. This study investigated the neuroprotective effects of nonerythropoietic mutant EPO (MEPO) on white matter and the underlying mechanism in middle-aged (9-month-old) male mice following cerebral ischemia. Middle-aged male C57 BL/6 mice were treated with MEPO (5000 IU/kg) or vehicle after middle cerebral artery occlusion (MCAO) and reperfusion. The specific inhibitor AG490 was used to block the JAK2/STAT3 pathway. Neurological function was assessed by beam walking and adhesive removal tests. Immunofluorescence staining and western blotting were used to assess the severity of white matter injury, phenotypic changes in the microglia and the expression of the signaling molecules. MEPO significantly improved neurobehavioral outcomes, alleviated brain tissue loss, and ameliorated white matter injury after MCAO compared with the vehicle group. Moreover, MEPO promoted oligodendrogenesis by shifting microglia toward M2 polarization by promoting JAK2/STAT3 activation and inhibiting the expression of C/EBPβ at 14 days after cerebral ischemia-reperfusion. However, the MEPO's effect on microglial M2 polarization and oligodendrogenesis was largely suppressed by AG490 treatment. Collectively, these data indicate that MEPO treatment improves white matter integrity after cerebral ischemia, which may be partly explained by MEPO facilitating microglia toward the beneficial M2 phenotype to promote oligodendrogenesis via JAK2/STAT3 and the C/EBPβ signaling pathway. This study provides novel insight into MEPO treatment for ischemic stroke.
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Affiliation(s)
- Rongliang Wang
- Institute of Cerebrovascular Diseases Research and Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing 100053, China
| | - Sijia Zhang
- Institute of Cerebrovascular Diseases Research and Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing 100053, China
| | - Zhenhong Yang
- Institute of Cerebrovascular Diseases Research and Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing 100053, China
| | - Yangmin Zheng
- Institute of Cerebrovascular Diseases Research and Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing 100053, China
| | - Feng Yan
- Institute of Cerebrovascular Diseases Research and Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing 100053, China
| | - Zhen Tao
- Institute of Cerebrovascular Diseases Research and Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing 100053, China
| | - Junfen Fan
- Institute of Cerebrovascular Diseases Research and Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing 100053, China
| | - Haiping Zhao
- Institute of Cerebrovascular Diseases Research and Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing 100053, China
| | - Ziping Han
- Institute of Cerebrovascular Diseases Research and Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing 100053, China.
| | - Yumin Luo
- Institute of Cerebrovascular Diseases Research and Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing 100053, China; Center of Stroke, Beijing Institute for Brain Disorders, Beijing 100053, China; Beijing Key Laboratory of Translational Medicine for Cerebrovascular Diseases, Beijing 100053, China.
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Ndoja A, Reja R, Lee SH, Webster JD, Ngu H, Rose CM, Kirkpatrick DS, Modrusan Z, Chen YJJ, Dugger DL, Gandham V, Xie L, Newton K, Dixit VM. Ubiquitin Ligase COP1 Suppresses Neuroinflammation by Degrading c/EBPβ in Microglia. Cell 2020; 182:1156-1169.e12. [PMID: 32795415 DOI: 10.1016/j.cell.2020.07.011] [Citation(s) in RCA: 68] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 06/09/2020] [Accepted: 07/10/2020] [Indexed: 12/21/2022]
Abstract
Dysregulated microglia are intimately involved in neurodegeneration, including Alzheimer's disease (AD) pathogenesis, but the mechanisms controlling pathogenic microglial gene expression remain poorly understood. The transcription factor CCAAT/enhancer binding protein beta (c/EBPβ) regulates pro-inflammatory genes in microglia and is upregulated in AD. We show expression of c/EBPβ in microglia is regulated post-translationally by the ubiquitin ligase COP1 (also called RFWD2). In the absence of COP1, c/EBPβ accumulates rapidly and drives a potent pro-inflammatory and neurodegeneration-related gene program, evidenced by increased neurotoxicity in microglia-neuronal co-cultures. Antibody blocking studies reveal that neurotoxicity is almost entirely attributable to complement. Remarkably, loss of a single allele of Cebpb prevented the pro-inflammatory phenotype. COP1-deficient microglia markedly accelerated tau-mediated neurodegeneration in a mouse model where activated microglia play a deleterious role. Thus, COP1 is an important suppressor of pathogenic c/EBPβ-dependent gene expression programs in microglia.
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Affiliation(s)
- Ada Ndoja
- Department of Physiological Chemistry, Genentech, South San Francisco, CA 94080, USA
| | - Rohit Reja
- Department of Bioinformatics and Computational Biology, Genentech, South San Francisco, CA 94080, USA
| | - Seung-Hye Lee
- Department of Neuroscience, Genentech, South San Francisco, CA 94080, USA
| | - Joshua D Webster
- Department of Pathology, Genentech, South San Francisco, CA 94080, USA
| | - Hai Ngu
- Department of Pathology, Genentech, South San Francisco, CA 94080, USA
| | - Christopher M Rose
- Department of Microchemistry, Proteomics, Lipidomics and Next Generation Sequencing, Genentech, South San Francisco, CA 94080, USA
| | - Donald S Kirkpatrick
- Department of Microchemistry, Proteomics, Lipidomics and Next Generation Sequencing, Genentech, South San Francisco, CA 94080, USA
| | - Zora Modrusan
- Department of Microchemistry, Proteomics, Lipidomics and Next Generation Sequencing, Genentech, South San Francisco, CA 94080, USA
| | - Ying-Jiun Jasmine Chen
- Department of Microchemistry, Proteomics, Lipidomics and Next Generation Sequencing, Genentech, South San Francisco, CA 94080, USA
| | - Debra L Dugger
- Department of Physiological Chemistry, Genentech, South San Francisco, CA 94080, USA
| | - Vineela Gandham
- Department of Biomedical Imaging, Genentech, South San Francisco, CA 94080, USA
| | - Luke Xie
- Department of Biomedical Imaging, Genentech, South San Francisco, CA 94080, USA
| | - Kim Newton
- Department of Physiological Chemistry, Genentech, South San Francisco, CA 94080, USA.
| | - Vishva M Dixit
- Department of Physiological Chemistry, Genentech, South San Francisco, CA 94080, USA.
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CCAAT/enhancer binding protein δ is a transcriptional repressor of α-synuclein. Cell Death Differ 2019; 27:509-524. [PMID: 31209363 DOI: 10.1038/s41418-019-0368-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 03/30/2019] [Accepted: 05/02/2019] [Indexed: 12/16/2022] Open
Abstract
α-Synuclein is the main component of Lewy bodies, the intracellular protein aggregates representing the histological hallmark of Parkinson's disease. Elevated α-synuclein levels and mutations in SNCA gene are associated with increased risk for Parkinson's disease. Despite this, little is known about the molecular mechanisms regulating SNCA transcription. CCAAT/enhancer binding protein (C/EBP) β and δ are b-zip transcription factors that play distinct roles in neurons and glial cells. C/EBPβ overexpression increases SNCA expression in neuroblastoma cells and putative C/EBPβ and δ binding sites are present in the SNCA genomic region suggesting that these proteins could regulate SNCA transcription. Based on these premises, the goal of this study was to determine if C/EBPβ and δ regulate the expression of SNCA. We first observed that α-synuclein CNS expression was not affected by C/EBPβ deficiency but it was markedly increased in C/EBPδ-deficient mice. This prompted us to characterize further the role of C/EBPδ in SNCA transcription. C/EBPδ absence led to the in vivo increase of α-synuclein in all brain regions analyzed, both at mRNA and protein level, and in primary neuronal cultures. In agreement with this, CEBPD overexpression in neuroblastoma cells and in primary neuronal cultures markedly reduced SNCA expression. ChIP experiments demonstrated C/EBPδ binding to the SNCA genomic region of mice and humans and luciferase experiments showed decreased expression of a reporter gene attributable to C/EBPδ binding to the SNCA promoter. Finally, decreased CEBPD expression was observed in the substantia nigra and in iPSC-derived dopaminergic neurons from Parkinson patients resulting in a significant negative correlation between SNCA and CEBPD levels. This study points to C/EBPδ as an important repressor of SNCA transcription and suggests that reduced C/EBPδ neuronal levels could be a pathogenic factor in Parkinson's disease and other synucleinopathies and C/EBPδ activity a potential pharmacological target for these neurological disorders.
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Valente T, Serratosa J, Perpiñá U, Saura J, Solà C. Alterations in CD200-CD200R1 System during EAE Already Manifest at Presymptomatic Stages. Front Cell Neurosci 2017; 11:129. [PMID: 28522962 PMCID: PMC5415594 DOI: 10.3389/fncel.2017.00129] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Accepted: 04/18/2017] [Indexed: 11/13/2022] Open
Abstract
In the brain of patients with multiple sclerosis, activated microglia/macrophages appear in active lesions and in normal appearing white matter. However, whether they play a beneficial or a detrimental role in the development of the pathology remains a controversial issue. The production of pro-inflammatory molecules by chronically activated microglial cells is suggested to contribute to the progression of neurodegenerative processes in neurological disease. In the healthy brain, neurons control glial activation through several inhibitory mechanisms, such as the CD200-CD200R1 interaction. Therefore, we studied whether alterations in the CD200-CD200R1 system might underlie the neuroinflammation in an experimental autoimmune encephalomyelitis (EAE) model of multiple sclerosis. We determined the time course of CD200 and CD200R1 expression in the brain and spinal cord of an EAE mouse model from presymptomatic to late symptomatic stages. We also assessed the correlation with associated glial activation, inflammatory response and EAE severity. Alterations in CD200 and CD200R1 expression were mainly observed in spinal cord regions in the EAE model, mostly a decrease in CD200 and an increase in CD200R1 expression. A decrease in the expression of the mRNA encoding a full CD200 protein was detected before the onset of clinical signs, and remained thereafter. A decrease in CD200 protein expression was observed from the onset of clinical signs. By contrast, CD200R1 expression increased at EAE onset, when a glial reaction associated with the production of pro- and anti-inflammatory markers occurred, and continued to be elevated during the pathology. Moreover, the magnitude of the alterations correlated with severity of the EAE mainly in spinal cord. These results suggest that neuronal-microglial communication through CD200-CD200R1 interaction is compromised in EAE. The early decreases in CD200 expression in EAE suggest that this downregulation might also occur in the initial phases of multiple sclerosis, and that this early neuronal dysfunction might facilitate the development of neuroinflammation. The increased CD200R1 expression in the EAE model highlights the potential use of targeted agonist molecules as therapeutic tools to control neuroinflammation. In summary, the CD200-CD200R1 system is a potential therapeutic target in multiple sclerosis, and CD200R1 agonists are molecules that may be worth developing in this context.
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Affiliation(s)
- Tony Valente
- Department of Cerebral Ischemia and Neurodegeneration, Institut D'Investigacions Biomèdiques de Barcelona-Consejo Superior de Investigaciones Científicas (CSIC), Institut D'Investigacions Biomèdiques August-Pi i Sunyer (IDIBAPS)Barcelona, Spain
| | - Joan Serratosa
- Department of Cerebral Ischemia and Neurodegeneration, Institut D'Investigacions Biomèdiques de Barcelona-Consejo Superior de Investigaciones Científicas (CSIC), Institut D'Investigacions Biomèdiques August-Pi i Sunyer (IDIBAPS)Barcelona, Spain
| | - Unai Perpiñá
- Department of Cerebral Ischemia and Neurodegeneration, Institut D'Investigacions Biomèdiques de Barcelona-Consejo Superior de Investigaciones Científicas (CSIC), Institut D'Investigacions Biomèdiques August-Pi i Sunyer (IDIBAPS)Barcelona, Spain
| | - Josep Saura
- Biochemistry and Molecular Biology Unit, School of Medicine, Institut D'Investigacions Biomèdiques August-Pi i Sunyer (IDIBAPS), University of BarcelonaBarcelona, Spain
| | - Carme Solà
- Department of Cerebral Ischemia and Neurodegeneration, Institut D'Investigacions Biomèdiques de Barcelona-Consejo Superior de Investigaciones Científicas (CSIC), Institut D'Investigacions Biomèdiques August-Pi i Sunyer (IDIBAPS)Barcelona, Spain
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Pulido-Salgado M, Vidal-Taboada JM, Garcia Diaz-Barriga G, Serratosa J, Valente T, Castillo P, Matalonga J, Straccia M, Canals JM, Valledor A, Solà C, Saura J. Myeloid C/EBPβ deficiency reshapes microglial gene expression and is protective in experimental autoimmune encephalomyelitis. J Neuroinflammation 2017; 14:54. [PMID: 28302135 PMCID: PMC5356255 DOI: 10.1186/s12974-017-0834-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Accepted: 03/06/2017] [Indexed: 12/31/2022] Open
Abstract
Background CCAAT/enhancer binding protein β (C/EBPβ) is a transcription factor that regulates the expression of important pro-inflammatory genes in microglia. Mice deficient for C/EBPβ show protection against excitotoxic and ischemic CNS damage, but the involvement in this neuroprotective effect of the various C/EBPβ-expressing cell types is not solved. Since C/EBPβ-deficient microglia show attenuated neurotoxicity in culture, we hypothesized that specific C/EBPβ deficiency in microglia could be neuroprotective in vivo. In this study, we have tested this hypothesis by generating mice with myeloid C/EBPβ deficiency. Methods Mice with myeloid C/EBPβ deficiency were generated by crossing LysMCre and C/EBPβfl/fl mice. Primary microglial cultures from C/EBPβfl/fl and LysMCre-C/EBPβfl/fl mice were treated with lipopolysaccharide ± interferon γ (IFNγ) for 6 h, and gene expression was analyzed by RNA sequencing. Gene expression and C/EBPβ deletion were analyzed in vivo in microglia isolated from the brains of C/EBPβfl/fl and LysMCre-C/EBPβfl/fl mice treated systemically with lipolysaccharide or vehicle. Mice of LysMCre-C/EBPβfl/fl or control genotypes were subjected to experimental autoimmune encephalitis and analyzed for clinical signs for 52 days. One- or two-way ANOVA or Kruskal–Wallis with their appropriate post hoc tests were used. Results LysMCre-C/EBPβfl/fl mice showed an efficiency of C/EBPβ deletion in microglia of 100 and 90% in vitro and in vivo, respectively. These mice were devoid of female infertility, perinatal mortality and reduced lifespan that are associated to full C/EBPβ deficiency. Transcriptomic analysis of C/EBPβ-deficient primary microglia revealed C/EBPβ-dependent expression of 1068 genes, significantly enriched in inflammatory and innate immune responses GO terms. In vivo, microglial expression of the pro-inflammatory genes Cybb, Ptges, Il23a, Tnf and Csf3 induced by systemic lipopolysaccharide injection was also blunted by C/EBPβ deletion. CNS expression of C/EBPβ was upregulated in experimental autoimmune encephalitis and in multiple sclerosis samples. Finally, LysMCre-C/EBPβfl/fl mice showed robust attenuation of clinical signs in experimental autoimmune encephalitis. Conclusion This study provides new data that support a central role for C/EBPβ in the biology of activated microglia, and it offers proof of concept for the therapeutic potential of microglial C/EBPβ inhibition in multiple sclerosis. Electronic supplementary material The online version of this article (doi:10.1186/s12974-017-0834-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Marta Pulido-Salgado
- Department of Biomedicine, Biochemistry and Molecular Biology Unit, School of Medicine, University of Barcelona, IDIBAPS, Barcelona, Spain.,Institute of Neurosciences, University of Barcelona, Barcelona, Spain
| | - Jose M Vidal-Taboada
- Department of Biomedicine, Biochemistry and Molecular Biology Unit, School of Medicine, University of Barcelona, IDIBAPS, Barcelona, Spain.,Institute of Neurosciences, University of Barcelona, Barcelona, Spain
| | - Gerardo Garcia Diaz-Barriga
- Department of Biomedicine, Histology Unit, School of Medicine, University of Barcelona, IDIBAPS, Barcelona, Spain.,Institute of Neurosciences, University of Barcelona, Barcelona, Spain
| | - Joan Serratosa
- Department of Cerebral Ischemia and Neurodegeneration, Institut d'Investigacions Biomèdiques de Barcelona, CSIC, IDIBAPS, Barcelona, Spain
| | - Tony Valente
- Department of Biomedicine, Biochemistry and Molecular Biology Unit, School of Medicine, University of Barcelona, IDIBAPS, Barcelona, Spain.,Department of Cerebral Ischemia and Neurodegeneration, Institut d'Investigacions Biomèdiques de Barcelona, CSIC, IDIBAPS, Barcelona, Spain.,Institute of Neurosciences, University of Barcelona, Barcelona, Spain
| | - Paola Castillo
- Department of Pathology, Hospital Clinic, ISGlobal, CRESIB, Barcelona, Spain
| | - Jonathan Matalonga
- Department of Physiology and Immunology, School of Biology, University of Barcelona, Barcelona, Catalonia, Spain
| | - Marco Straccia
- Department of Biomedicine, Biochemistry and Molecular Biology Unit, School of Medicine, University of Barcelona, IDIBAPS, Barcelona, Spain.,Department of Biomedicine, Histology Unit, School of Medicine, University of Barcelona, IDIBAPS, Barcelona, Spain.,Department of Cerebral Ischemia and Neurodegeneration, Institut d'Investigacions Biomèdiques de Barcelona, CSIC, IDIBAPS, Barcelona, Spain.,Institute of Neurosciences, University of Barcelona, Barcelona, Spain
| | - Josep M Canals
- Department of Biomedicine, Histology Unit, School of Medicine, University of Barcelona, IDIBAPS, Barcelona, Spain.,Institute of Neurosciences, University of Barcelona, Barcelona, Spain
| | - Annabel Valledor
- Department of Physiology and Immunology, School of Biology, University of Barcelona, Barcelona, Catalonia, Spain
| | - Carme Solà
- Department of Cerebral Ischemia and Neurodegeneration, Institut d'Investigacions Biomèdiques de Barcelona, CSIC, IDIBAPS, Barcelona, Spain
| | - Josep Saura
- Department of Biomedicine, Biochemistry and Molecular Biology Unit, School of Medicine, University of Barcelona, IDIBAPS, Barcelona, Spain. .,Institute of Neurosciences, University of Barcelona, Barcelona, Spain.
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Souza PVSD, Pinto WBVDR, Rezende FM, Oliveira ASB. Far beyond the motor neuron: the role of glial cells in amyotrophic lateral sclerosis. ARQUIVOS DE NEURO-PSIQUIATRIA 2016; 74:849-854. [PMID: 27759812 DOI: 10.1590/0004-282x20160117] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2016] [Accepted: 06/13/2016] [Indexed: 01/22/2023]
Abstract
Motor neuron disease is one of the major groups of neurodegenerative diseases, mainly represented by amyotrophic lateral sclerosis. Despite wide genetic and biochemical data regarding its pathophysiological mechanisms, motor neuron disease develops under a complex network of mechanisms not restricted to the unique functions of the alpha motor neurons but which actually involve diverse functions of glial cell interaction. This review aims to expose some of the leading roles of glial cells in the physiological mechanisms of neuron-glial cell interactions and the mechanisms related to motor neuron survival linked to glial cell functions.
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Affiliation(s)
| | | | - Flávio Moura Rezende
- Universidade Federal de São Paulo, Departamento de Neurologia e Neurocirurgia, São Paulo SP, Brasil
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Inflammatory transcription factors as activation markers and functional readouts in immune-to-brain communication. Brain Behav Immun 2016; 54:1-14. [PMID: 26348582 DOI: 10.1016/j.bbi.2015.09.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Revised: 08/31/2015] [Accepted: 09/04/2015] [Indexed: 02/06/2023] Open
Abstract
Immune-to-brain communication pathways involve humoral mediators, including cytokines, central modulation by neuronal afferents and immune cell trafficking to the brain. During systemic inflammation these pathways contribute to mediating brain-controlled sickness symptoms including fever. Experimentally, activation of these signaling pathways can be mimicked and studied when injecting animals with pathogen associated molecular patterns (PAMPS). One central component of the brain inflammatory response, which leads, for example, to fever induction, is transcriptional activation of brain cells via cytokines and PAMPS. We and others have studied the spatiotemporal activation and the physiological significance of transcription factors for the induction of inflammation within the brain and the manifestation of fever. Evidence has revealed a role of nuclear factor (NF)κB in the initiation, signal transducer and activator of transcription (STAT)3 in the maintenance and NF-interleukin (IL)6 in the maintenance or even termination of brain-inflammation and fever. Moreover, psychological stressors, such as exposure to a novel environment, leads to increased body core temperature and genomic NF-IL6-activation, suggesting a potential use of NF-IL6-immunohistochemistry as a multimodal brain cell activation marker and a role for NF-IL6 for differential brain activity. In addition, the nutritional status, as reflected by circulating levels of the cytokine-like hormone leptin, influence immune-to-brain communication and age-dependent changes in LPS-induced fever. Overall, transcription factors remain therapeutically important targets for the treatment of brain-inflammation and fever induction during infectious/non-infectious inflammatory and psychological stress. However, the exact physiological role and significance of these transcription factors requires to be further investigated.
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MicroRNA-125b regulates microglia activation and motor neuron death in ALS. Cell Death Differ 2016; 23:531-41. [PMID: 26794445 PMCID: PMC5072447 DOI: 10.1038/cdd.2015.153] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 09/24/2015] [Accepted: 10/23/2015] [Indexed: 12/11/2022] Open
Abstract
Understanding the means by which microglia self-regulate the neuroinflammatory response helps modulating their reaction during neurodegeneration. In amyotrophic lateral sclerosis (ALS), classical NF-κB pathway is related to persistent microglia activation and motor neuron injury; however, mechanisms of negative control of NF-κB activity remain unexplored. One of the major players in the termination of classical NF-κB pathway is the ubiquitin-editing enzyme A20, which has recognized anti-inflammatory functions. Lately, microRNAs are emerging as potent fine-tuners of neuroinflammation and reported to be regulated in ALS, for instance, by purinergic P2X7 receptor activation. In this work, we uncover an interplay between miR-125b and A20 protein in the modulation of classical NF-κB signaling in microglia. In particular, we establish the existence of a pathological circuit in which termination of A20 function by miR-125b strengthens and prolongs the noxious P2X7 receptor-dependent activation of NF-κB in microglia, with deleterious consequences on motor neurons. We prove that, by restoring A20 levels, miR-125b inhibition then sustains motor neuron survival. These results introduce miR-125b as a key mediator of microglia dynamics in ALS.
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Jeyachandran A, Mertens B, McKissick EA, Mitchell CS. Type I Vs. Type II Cytokine Levels as a Function of SOD1 G93A Mouse Amyotrophic Lateral Sclerosis Disease Progression. Front Cell Neurosci 2015; 9:462. [PMID: 26648846 PMCID: PMC4664727 DOI: 10.3389/fncel.2015.00462] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Accepted: 11/13/2015] [Indexed: 01/01/2023] Open
Abstract
Amyotrophic Lateral Sclerosis (ALS) is a fatal motoneuron disease that is characterized by the degradation of neurons throughout the central nervous system. Inflammation have been cited a key contributor to ALS neurodegeneration, but the timeline of cytokine upregulation remains unresolved. The goal of this study was to temporally examine the correlation between the varying levels of pro-inflammatory type I cytokines (IL-1β, IL-1α, IL-12, TNF-α, and GFAP) and anti-inflammatory type II cytokines (IL-4, IL-6, IL-10) throughout the progression of ALS in the SOD1 G93A mouse model. Cytokine level data from high copy SOD1 G93A transgenic mice was collected from 66 peer-reviewed studies. For each corresponding experimental time point, the ratio of transgenic to wild type (TG/WT) cytokine was calculated. One-way ANOVA and t-tests with Bonferonni correction were used to analyze the data. Meta-analysis was performed for four discrete stages: early, pre-onset, post-onset, and end stage. A significant increase in TG cytokine levels was found when compared to WT cytokine levels across the entire SOD1 G93A lifespan for majority of the cytokines. The rates of change of the individual cytokines, and type I and type II were not significantly different; however, the mean fold change of type I was expressed at significantly higher levels than type II levels across all stages with the difference between the means becoming more pronounced at the end stage. An overexpression of cytokines occurred both before and after the onset of ALS symptoms. The trend between pro-inflammatory type I and type II cytokine mean levels indicate a progressive instability of the dynamic balance between pro- and anti-inflammatory cytokines as anti-inflammatory cytokines fail to mediate the pronounced increase in pro-inflammatory cytokines. Very early immunoregulatory treatment is necessary to successfully interrupt ALS-induced neuroinflammation.
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Affiliation(s)
- Amilia Jeyachandran
- Department of Biomedical Engineering, Georgia Institute of Technology and Emory University Atlanta, GA, USA
| | - Benjamin Mertens
- Department of Biomedical Engineering, Georgia Institute of Technology and Emory University Atlanta, GA, USA
| | - Eric A McKissick
- Department of Biomedical Engineering, Georgia Institute of Technology and Emory University Atlanta, GA, USA
| | - Cassie S Mitchell
- Department of Biomedical Engineering, Georgia Institute of Technology and Emory University Atlanta, GA, USA
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Pulido-Salgado M, Vidal-Taboada JM, Saura J. C/EBPβ and C/EBPδ transcription factors: Basic biology and roles in the CNS. Prog Neurobiol 2015; 132:1-33. [PMID: 26143335 DOI: 10.1016/j.pneurobio.2015.06.003] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 05/08/2015] [Accepted: 06/16/2015] [Indexed: 02/01/2023]
Abstract
CCAAT/enhancer binding protein (C/EBP) β and C/EBPδ are transcription factors of the basic-leucine zipper class which share phylogenetic, structural and functional features. In this review we first describe in depth their basic molecular biology which includes fascinating aspects such as the regulated use of alternative initiation codons in the C/EBPβ mRNA. The physical interactions with multiple transcription factors which greatly opens the number of potentially regulated genes or the presence of at least five different types of post-translational modifications are also remarkable molecular mechanisms that modulate C/EBPβ and C/EBPδ function. In the second part, we review the present knowledge on the localization, expression changes and physiological roles of C/EBPβ and C/EBPδ in neurons, astrocytes and microglia. We conclude that C/EBPβ and C/EBPδ share two unique features related to their role in the CNS: whereas in neurons they participate in memory formation and synaptic plasticity, in glial cells they regulate the pro-inflammatory program. Because of their role in neuroinflammation, C/EBPβ and C/EBPδ in microglia are potential targets for treatment of neurodegenerative disorders. Any strategy to reduce C/EBPβ and C/EBPδ activity in neuroinflammation needs to take into account its potential side-effects in neurons. Therefore, cell-specific treatments will be required for the successful application of this strategy.
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Affiliation(s)
- Marta Pulido-Salgado
- Biochemistry and Molecular Biology Unit, School of Medicine, University of Barcelona, IDIBAPS, Casanova 143, planta 3, 08036 Barcelona, Spain
| | - Jose M Vidal-Taboada
- Biochemistry and Molecular Biology Unit, School of Medicine, University of Barcelona, IDIBAPS, Casanova 143, planta 3, 08036 Barcelona, Spain
| | - Josep Saura
- Biochemistry and Molecular Biology Unit, School of Medicine, University of Barcelona, IDIBAPS, Casanova 143, planta 3, 08036 Barcelona, Spain.
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Miller RG, Zhang R, Block G, Katz J, Barohn R, Kasarskis E, Forshew D, Gopalakrishnan V, McGrath MS. NP001 regulation of macrophage activation markers in ALS: a phase I clinical and biomarker study. Amyotroph Lateral Scler Frontotemporal Degener 2014; 15:601-9. [PMID: 25192333 DOI: 10.3109/21678421.2014.951940] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
This is a phase I, placebo-controlled, single ascending dose safety and tolerability study of NP001 in patients with ALS. NP001 is a novel regulator of inflammatory macrophages and monocytes. As ALS progression is thought to be related to neuroinflammation, an additional objective of the study was to assess the effects of NP001 administration on monocyte activation markers. Thirty-two ALS patients were enrolled and received either placebo (eight) or one of four (six at each dose) ascending single i.v. doses (0.2, 0.8, 1.6 and 3.2 mg/kg NP001). Patients were monitored for safety, and blood monocyte immune activation markers CD16 and HLA-DR were assessed pre- and 24 h post-dosing. Changes from baseline were calculated. Results showed that NP001 was generally safe and well tolerated. Importantly, a single dose of NP001 caused a dose-dependent reduction in expression of monocyte CD16, a marker of monocyte activation/inflammation. Additionally, monocyte HLA-DR expression was also decreased in those patients with elevated values at baseline. In conclusion, these data indicate that NP001 has an acute effect on inflammatory monocytes in ALS patient blood. The potential for modulation of inflammation in the context of ALS disease progression will require further study with long-term follow-up.
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Li MD, Burns TC, Morgan AA, Khatri P. Integrated multi-cohort transcriptional meta-analysis of neurodegenerative diseases. Acta Neuropathol Commun 2014; 2:93. [PMID: 25187168 PMCID: PMC4167139 DOI: 10.1186/s40478-014-0093-y] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Accepted: 07/23/2014] [Indexed: 01/11/2023] Open
Abstract
Introduction Neurodegenerative diseases share common pathologic features including neuroinflammation, mitochondrial dysfunction and protein aggregation, suggesting common underlying mechanisms of neurodegeneration. We undertook a meta-analysis of public gene expression data for neurodegenerative diseases to identify a common transcriptional signature of neurodegeneration. Results Using 1,270 post-mortem central nervous system tissue samples from 13 patient cohorts covering four neurodegenerative diseases, we identified 243 differentially expressed genes, which were similarly dysregulated in 15 additional patient cohorts of 205 samples including seven neurodegenerative diseases. This gene signature correlated with histologic disease severity. Metallothioneins featured prominently among differentially expressed genes, and functional pathway analysis identified specific convergent themes of dysregulation. MetaCore network analyses revealed various novel candidate hub genes (e.g. STAU2). Genes associated with M1-polarized macrophages and reactive astrocytes were strongly enriched in the meta-analysis data. Evaluation of genes enriched in neurons revealed 70 down-regulated genes, over half not previously associated with neurodegeneration. Comparison with aging brain data (3 patient cohorts, 221 samples) revealed 53 of these to be unique to neurodegenerative disease, many of which are strong candidates to be important in neuropathogenesis (e.g. NDN, NAP1L2). ENCODE ChIP-seq analysis predicted common upstream transcriptional regulators not associated with normal aging (REST, RBBP5, SIN3A, SP2, YY1, ZNF143, IKZF1). Finally, we removed genes common to neurodegeneration from disease-specific gene signatures, revealing uniquely robust immune response and JAK-STAT signaling in amyotrophic lateral sclerosis. Conclusions Our results implicate pervasive bioenergetic deficits, M1-type microglial activation and gliosis as unifying themes of neurodegeneration, and identify numerous novel genes associated with neurodegenerative processes. Electronic supplementary material The online version of this article (doi:10.1186/s40478-014-0093-y) contains supplementary material, which is available to authorized users.
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CCAAT-enhancer binding protein-β expression and elevation in Alzheimer's disease and microglial cell cultures. PLoS One 2014; 9:e86617. [PMID: 24466171 PMCID: PMC3899300 DOI: 10.1371/journal.pone.0086617] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Accepted: 12/16/2013] [Indexed: 01/24/2023] Open
Abstract
CCAAT-enhancer binding proteins are transcription factors that help to regulate a wide range of inflammatory mediators, as well as several key elements of energy metabolism. Because C/EBPs are expressed by rodent astrocytes and microglia, and because they are induced by pro-inflammatory cytokines that are chronically upregulated in the Alzheimer’s disease (AD) cortex, we have investigated whether C/EBPs are expressed and upregulated in the AD cortex. Here, we demonstrate for the first time that C/EBPβ can be detected by Western blots in AD and nondemented elderly (ND) cortex, and that it is significantly increased in AD cortical samples. In situ, C/EBPβ localizes immunohistochemically to microglia. In microglia cultured from rapid autopsies of elderly patient’s brains and in the BV-2 murine microglia cell line, we have shown that C/EBPβ can be upregulated by C/EBP-inducing cytokines or lipopolysaccharide and exhibits nuclear translocation possibly indicating functional activity. Given the known co-regulatory role of C/EBPs in pivotal inflammatory mechanisms, many of which are present in AD, we propose that upregulation of C/EBPs in the AD brain could be an important orchestrator of pathogenic changes.
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Pan HC, Yang CN, Hung YW, Lee WJ, Tien HR, Shen CC, Sheehan J, Chou CT, Sheu ML. Reciprocal modulation of C/EBP-α and C/EBP-β by IL-13 in activated microglia prevents neuronal death. Eur J Immunol 2013; 43:2854-65. [DOI: 10.1002/eji.201343301] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Revised: 06/08/2013] [Accepted: 07/19/2013] [Indexed: 01/16/2023]
Affiliation(s)
- Hung Chuan Pan
- Faculty of Medicine; School of Medicine; National Yang-Ming University; Taipei Taiwan
- Department of Neurosurgery; Taichung Veterans General Hospital; Taichung Taiwan
| | - Cheng Ning Yang
- Institute of Neuroscience; School of Life Science; National Yang-Ming University; Taipei Taiwan
| | - Yi Wen Hung
- Department of Education and Research; Taichung Veterans General Hospital; Taichung Taiwan
- Department of Veterinary Medicine; College of Veterinary Medicine; National Chung Hsing University; Taichung Taiwan
| | - Wen Jane Lee
- Department of Education and Research; Taichung Veterans General Hospital; Taichung Taiwan
| | - Hsing Ru Tien
- Institute of Biomedical Sciences; College of Life Science; National Chung Hsing University; Taichung Taiwan
| | - Chin Chang Shen
- Institute of Nuclear Energy Research; Atomic Energy Council; Longtan Taoyuan Taiwan
| | - Jason Sheehan
- Department of Neurological Surgery; University of Virginia Health System; Charlottesville VA USA
| | - Chiang Ting Chou
- School of Nursing; Chang Gung University of Science and Technology; Chiayi Campus Taiwan
| | - Meei Ling Sheu
- Department of Education and Research; Taichung Veterans General Hospital; Taichung Taiwan
- Institute of Biomedical Sciences; College of Life Science; National Chung Hsing University; Taichung Taiwan
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Smith AM, Gibbons HM, Oldfield RL, Bergin PM, Mee EW, Curtis MA, Faull RLM, Dragunow M. M-CSF increases proliferation and phagocytosis while modulating receptor and transcription factor expression in adult human microglia. J Neuroinflammation 2013; 10:85. [PMID: 23866312 PMCID: PMC3729740 DOI: 10.1186/1742-2094-10-85] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Accepted: 07/09/2013] [Indexed: 11/18/2022] Open
Abstract
Background Microglia are the primary immune cells of the brain whose phenotype largely depends on their surrounding micro-environment. Microglia respond to a multitude of soluble molecules produced by a variety of brain cells. Macrophage colony-stimulating factor (M-CSF) is a cytokine found in the brain whose receptor is expressed by microglia. Previous studies suggest a critical role for M-CSF in brain development and normal functioning as well as in several disease processes involving neuroinflammation. Methods Using biopsy tissue from patients with intractable temporal epilepsy and autopsy tissue, we cultured primary adult human microglia to investigate their response to M-CSF. Mixed glial cultures were treated with 25 ng/ml M-CSF for 96 hours. Proliferation and phagocytosis assays, and high through-put immunocytochemistry, microscopy and image analysis were performed to investigate microglial phenotype and function. Results We found that the phenotype of primary adult human microglia was markedly changed following exposure to M-CSF. A greater number of microglia were present in the M-CSF- treated cultures as the percentage of proliferating (BrdU and Ki67-positive) microglia was greatly increased. A number of changes in protein expression occurred following M-CSF treatment, including increased transcription factors PU.1 and C/EBPβ, increased DAP12 adaptor protein, increased M-CSF receptor (CSF-1R) and IGF-1 receptor, and reduced HLA-DP, DQ, DR antigen presentation protein. Furthermore, a distinct morphological change was observed with elongation of microglial processes. These changes in phenotype were accompanied by a functional increase in phagocytosis of Aβ1-42 peptide. Conclusions We show here that the cytokine M-CSF dramatically influences the phenotype of adult human microglia. These results pave the way for future investigation of M-CSF-related targets for human therapeutic benefit.
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Affiliation(s)
- Amy M Smith
- Department of Pharmacology and Clinical Pharmacology, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
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21
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Valente T, Straccia M, Gresa-Arribas N, Dentesano G, Tusell JM, Serratosa J, Mancera P, Solà C, Saura J. CCAAT/enhancer binding protein δ regulates glial proinflammatory gene expression. Neurobiol Aging 2013; 34:2110-24. [PMID: 23523267 DOI: 10.1016/j.neurobiolaging.2013.02.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Revised: 02/06/2013] [Accepted: 02/10/2013] [Indexed: 12/22/2022]
Abstract
The transcription factor CCAAT/enhancer binding protein δ (C/EBPδ) is expressed in activated astrocytes and microglia and can regulate the expression of potentially detrimental proinflammatory genes. The objective of this study was to determine the role of C/EBPδ in glial activation. To this end, glial activation was analyzed in primary glial cultures and in the central nervous system from wild type and C/EBPδ(-/-) mice. In vitro studies showed that the expression of proinflammatory genes nitric oxide (NO)synthase-2, cyclooxygenase-2, and interleukin (IL)-6 in glial cultures, and the neurotoxicity elicited by microglia in neuron-microglia cocultures, were decreased in the absence of C/EBPδ when cultures were treated with lipopolysaccharide (LPS) and interferon γ, but not with LPS alone. In C/EBPδ(-/-) mice, systemic LPS-induced brain expression of NO synthase-2, tumor necrosis factor-α, IL-1β, and IL-6 was attenuated. Finally, increased C/EBPδ nuclear expression was observed in microglial cells from amyotrophic lateral sclerosis patients and G93A-SOD1 mice spinal cord. These results demonstrate that C/EBPδ plays a key role in the regulation of proinflammatory gene expression in glial activation and suggest that C/EBPδ inhibition has potential for the treatment of neurodegenerative disorders, in particular, amyotrophic lateral sclerosis.
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Affiliation(s)
- Tony Valente
- Biochemistry and Molecular Biology Unit, School of Medicine, University of Barcelona, IDIBAPS, Barcelona, Spain
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22
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Figueroa-Romero C, Hur J, Bender DE, Delaney CE, Cataldo MD, Smith AL, Yung R, Ruden DM, Callaghan BC, Feldman EL. Identification of epigenetically altered genes in sporadic amyotrophic lateral sclerosis. PLoS One 2012; 7:e52672. [PMID: 23300739 PMCID: PMC3530456 DOI: 10.1371/journal.pone.0052672] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2012] [Accepted: 11/19/2012] [Indexed: 12/12/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a terminal disease involving the progressive degeneration of motor neurons within the motor cortex, brainstem and spinal cord. Most cases are sporadic (sALS) with unknown causes suggesting that the etiology of sALS may not be limited to the genotype of patients, but may be influenced by exposure to environmental factors. Alterations in epigenetic modifications are likely to play a role in disease onset and progression in ALS, as aberrant epigenetic patterns may be acquired throughout life. The aim of this study was to identify epigenetic marks associated with sALS. We hypothesize that epigenetic modifications may alter the expression of pathogenesis-related genes leading to the onset and progression of sALS. Using ELISA assays, we observed alterations in global methylation (5 mC) and hydroxymethylation (5 HmC) in postmortem sALS spinal cord but not in whole blood. Loci-specific differentially methylated and expressed genes in sALS spinal cord were identified by genome-wide 5mC and expression profiling using high-throughput microarrays. Concordant direction, hyper- or hypo-5mC with parallel changes in gene expression (under- or over-expression), was observed in 112 genes highly associated with biological functions related to immune and inflammation response. Furthermore, literature-based analysis identified potential associations among the epigenes. Integration of methylomics and transcriptomics data successfully revealed methylation changes in sALS spinal cord. This study represents an initial identification of epigenetic regulatory mechanisms in sALS which may improve our understanding of sALS pathogenesis for the identification of biomarkers and new therapeutic targets.
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Affiliation(s)
- Claudia Figueroa-Romero
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Junguk Hur
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Diane E. Bender
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Colin E. Delaney
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Michael D. Cataldo
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Andrea L. Smith
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Raymond Yung
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Douglas M. Ruden
- Institute of Environmental Health Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, Detroit, Michigan, United States of America
| | - Brian C. Callaghan
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Eva L. Feldman
- Department of Neurology, University of Michigan, Ann Arbor, Michigan, United States of America
- National Center for Integrative Biomedical Informatics, University of Michigan, Ann Arbor, Michigan, United States of America
- * E-mail:
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Neuroinflammation as the proximate cause of signature pathogenic pattern progression in amyotrophic lateral sclerosis, AIDS, and multiple sclerosis. PATHOLOGY RESEARCH INTERNATIONAL 2012; 2012:169270. [PMID: 23304639 PMCID: PMC3529499 DOI: 10.1155/2012/169270] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 07/15/2012] [Accepted: 11/12/2012] [Indexed: 12/13/2022]
Abstract
The realization of injury to large motor neurons is embedded within contextual reference to the parallel pathways of apoptosis and necrosis of system-patterned evolution. A widespread loss of cell components occurs intracellularly and involves a reactive participation to a neuroinflammation that potentially is immunologically definable. In such terms, sporadic and hereditary forms of amyotrophic sclerosis are paralleled by the components of a reactive nature that involve the aggregation of proteins and conformational misfolding on the one hand and a powerful oxidative degradation that overwhelms the proteasome clearance mechanisms. In such terms, global participation is only one aspect of a disorder realization that induces the development of the defining systems of modulation and of injury that involves the systems of consequence as demonstrated by the overwhelming immaturity of the molecular variants of mutated superoxide dismutase. It is further to such processes of neuroinflammatory consequence that the immune system is integral to the reactive involvement of neurons as patterns of disease recognition and as the system biology of prevalent voluntarily motor character. It is highly significant to recognize various inflammatory states in the nervous system as prototype variability in phenotype expression and as incremental progression in pathogenesis. In fact a determining definition of amyotrophic lateral sclerosis is an incremental phenotype modulation within the pathways of the consequential loss and depletion of motor cell components in the first instance. Neuroinflammation proves a pattern of the contextual spread of such pathogenic progression in the realization of end-stage injury states involving neurons and neuronal networks.
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Dentesano G, Straccia M, Ejarque-Ortiz A, Tusell JM, Serratosa J, Saura J, Solà C. Inhibition of CD200R1 expression by C/EBP β in reactive microglial cells. J Neuroinflammation 2012; 9:165. [PMID: 22776069 PMCID: PMC3414764 DOI: 10.1186/1742-2094-9-165] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Accepted: 07/09/2012] [Indexed: 11/12/2022] Open
Abstract
Background In physiological conditions, it is postulated that neurons control microglial reactivity through a series of inhibitory mechanisms, involving either cell contact-dependent, soluble-factor-dependent or neurotransmitter-associated pathways. In the current study, we focus on CD200R1, a microglial receptor involved in one of these cell contact-dependent mechanisms. CD200R1 activation by its ligand, CD200 (mainly expressed by neurons in the central nervous system),is postulated to inhibit the pro-inflammatory phenotype of microglial cells, while alterations in CD200-CD200R1 signalling potentiate this phenotype. Little is known about the regulation of CD200R1 expression in microglia or possible alterations in the presence of pro-inflammatory stimuli. Methods Murine primary microglial cultures, mixed glial cultures from wild-type and CCAAT/enhancer binding protein β (C/EBPβ)-deficient mice, and the BV2 murine cell line overexpressing C/EBPβ were used to study the involvement of C/EBPβ transcription factor in the regulation of CD200R1 expression in response to a proinflammatory stimulus (lipopolysaccharide (LPS)). Binding of C/EBPβ to the CD200R1 promoter was determined by quantitative chromatin immunoprecipitation (qChIP). The involvement of histone deacetylase 1 in the control of CD200R1 expression by C/EBPβ was also determined by co-immunoprecipitation and qChIP. Results LPS treatment induced a decrease in CD200R1 mRNA and protein expression in microglial cells, an effect that was not observed in the absence of C/EBPβ. C/EBPβ overexpression in BV2 cells resulted in a decrease in basal CD200R1 mRNA and protein expression. In addition, C/EBPβ binding to the CD200R1 promoter was observed in LPS-treated but not in control glial cells, and also in control BV2 cells overexpressing C/EBPβ. Finally, we observed that histone deacetylase 1 co-immunoprecipitated with C/EBPβ and showed binding to a C/EBPβ consensus sequence of the CD200R1 promoter in LPS-treated glial cells. Moreover, histone deacetylase 1 inhibitors reversed the decrease in CD200R1 expression induced by LPS treatment. Conclusions CD200R1 expression decreases in microglial cells in the presence of a pro-inflammatory stimulus, an effect that is regulated, at least in part, by C/EBPβ. Histone deacetylase 1 may mediate C/EBPβ inhibition of CD200R1 expression, through a direct effect on C/EBPβ transcriptional activity and/or on chromatin structure.
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Affiliation(s)
- Guido Dentesano
- Department of Cerebral Ischemia and Neurodegeneration, Institut d'Investigacions Biomèdiques de Barcelona-Consejo Superior de Investigaciones Científicas (CSIC), Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
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