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Ren Q, Liu Z, Wu L, Yin G, Xie X, Kong W, Zhou J, Liu S. C/EBPβ: The structure, regulation, and its roles in inflammation-related diseases. Biomed Pharmacother 2023; 169:115938. [PMID: 38000353 DOI: 10.1016/j.biopha.2023.115938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 11/08/2023] [Accepted: 11/21/2023] [Indexed: 11/26/2023] Open
Abstract
Inflammation, a mechanism of the human body, has been implicated in many diseases. Inflammatory responses include the release of inflammatory mediators by activating various signaling pathways. CCAAT/enhancer binding protein β (C/EBPβ), a transcription factor in the C/EBP family, contains the leucine zipper (bZIP) domain. The expression of C/EBPβ is mediated at the transcriptional and post-translational levels, such as phosphorylation, acetylation, methylation, and SUMOylation. C/EBPβ has been involved in inflammatory responses by mediating several signaling pathways, such as MAPK/NF-κB and IL-6/JAK/STAT3 pathways. C/EBPβ plays an important role in the pathological development of inflammation-related diseases, such as osteoarthritis, pneumonia, hepatitis, inflammatory bowel diseases, and rheumatoid arthritis. Here, we comprehensively discuss the structure and biological effects of C/EBPβ and its role in inflammatory diseases.
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Affiliation(s)
- Qun Ren
- Department of Pharmacy, Gannan Medical University, Ganzhou 341000, China
| | - Zhaowen Liu
- Department of Pharmacy, Gannan Medical University, Ganzhou 341000, China
| | - Longhuo Wu
- Department of Pharmacy, Gannan Medical University, Ganzhou 341000, China
| | - Guoqiang Yin
- Ganzhou People's Hospital Affiliated to Nanchang University, Ganzhou 341000, China
| | - Xunlu Xie
- Department of Joint Surgery, Ganzhou People's Hospital, Ganzhou 341000, China
| | - Weihao Kong
- Department of Joint Surgery, Ganzhou People's Hospital, Ganzhou 341000, China
| | - Jianguo Zhou
- Department of Joint Surgery, Ganzhou People's Hospital, Ganzhou 341000, China
| | - Shiwei Liu
- Department of Joint Surgery, Ganzhou People's Hospital, Ganzhou 341000, China.
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Chen C, Liao J, Xia Y, Liu X, Jones R, Haran J, McCormick B, Sampson TR, Alam A, Ye K. Gut microbiota regulate Alzheimer's disease pathologies and cognitive disorders via PUFA-associated neuroinflammation. Gut 2022; 71:2233-2252. [PMID: 35017199 PMCID: PMC10720732 DOI: 10.1136/gutjnl-2021-326269] [Citation(s) in RCA: 162] [Impact Index Per Article: 81.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 12/07/2021] [Indexed: 12/12/2022]
Abstract
OBJECTIVE This study is to investigate the role of gut dysbiosis in triggering inflammation in the brain and its contribution to Alzheimer's disease (AD) pathogenesis. DESIGN We analysed the gut microbiota composition of 3×Tg mice in an age-dependent manner. We generated germ-free 3×Tg mice and recolonisation of germ-free 3×Tg mice with fecal samples from both patients with AD and age-matched healthy donors. RESULTS Microbial 16S rRNA sequencing revealed Bacteroides enrichment. We found a prominent reduction of cerebral amyloid-β plaques and neurofibrillary tangles pathology in germ-free 3×Tg mice as compared with specific-pathogen-free mice. And hippocampal RNAseq showed that inflammatory pathway and insulin/IGF-1 signalling in 3×Tg mice brain are aberrantly altered in the absence of gut microbiota. Poly-unsaturated fatty acid metabolites identified by metabolomic analysis, and their oxidative enzymes were selectively elevated, corresponding with microglia activation and inflammation. AD patients' gut microbiome exacerbated AD pathologies in 3×Tg mice, associated with C/EBPβ/asparagine endopeptidase pathway activation and cognitive dysfunctions compared with healthy donors' microbiota transplants. CONCLUSIONS These findings support that a complex gut microbiome is required for behavioural defects, microglia activation and AD pathologies, the gut microbiome contributes to pathologies in an AD mouse model and that dysbiosis of the human microbiome might be a risk factor for AD.
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Affiliation(s)
- Chun Chen
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia, USA
| | - Jianming Liao
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia, USA
- Department of Neurosurgery, Renmin Hospital, Wuhan University, Wuhan, Hubei, China
| | - Yiyuan Xia
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia, USA
| | - Xia Liu
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia, USA
| | - Rheinallt Jones
- Department of Pediatrics, Emory University, Atlanta, Georgia, USA
| | - John Haran
- Department of Emergency Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA
- Center for Microbiome Research, University of Massachusetts Medical School, Worcester, Massachusetts, USA
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Beth McCormick
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | | | - Ashfaqul Alam
- Microbiology, Immunology & Molecular Genetics, University of Kentucky, Lexington, Kentucky, USA
- Markey Cancer Center, University of Kentucky, Lexington, KY, USA
| | - Keqiang Ye
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia, USA
- Faculty of Life and Health Sciences, The Brain Cognition and Brain Disorders Institute (BCBDI), Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences, Shenzhen, Guangdong, China
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Mizuno K, Jeffries AR, Abel T, Giese KP. Long-lasting transcription in hippocampal area CA1 after contextual fear conditioning. Neurobiol Learn Mem 2020; 172:107250. [PMID: 32422278 DOI: 10.1016/j.nlm.2020.107250] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 04/27/2020] [Accepted: 05/12/2020] [Indexed: 01/25/2023]
Abstract
A fundamental question is how memory is stored for several weeks and even longer. A long-lasting increase in gene transcription has been suggested to mediate such long-term memory storage. Here, we used contextual fear conditioning in mice to search for lasting transcription that may contribute to long-term memory storage. Our study focussed on hippocampal area CA1, which has been suggested to have a role for at least one week in contextual fear memory. Using an unbiased microarray analysis followed by confirmatory quantitative real-time PCR, we identified an upregulation of two transcription factors, Fosl2 and Nfil3, which lasted for seven days after conditioning. To our knowledge these are the longest transcriptional changes ever detected in the hippocampus after contextual fear conditioning. Thus, our findings suggest novel transcriptional candidates for long-term memory storage.
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Affiliation(s)
- Keiko Mizuno
- Maurice Wohl Clinical Neuroscience Institute, Department of Basic and Clinical Neuroscience, King's College London, UK.
| | - Aaron R Jeffries
- Biosciences, College of Life and Environmental Sciences, Geoffrey Pope, University of Exeter, Stocker Road, Exeter, EX4 4QD, UK
| | - Ted Abel
- Department of Molecular Physiology and Biophysics, Iowa Neuroscience Institute, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - K Peter Giese
- Maurice Wohl Clinical Neuroscience Institute, Department of Basic and Clinical Neuroscience, King's College London, UK.
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Weathington N, O’Brien ME, Radder J, Whisenant TC, Bleecker ER, Busse WW, Erzurum SC, Gaston B, Hastie AT, Jarjour NN, Meyers DA, Milosevic J, Moore WC, Tedrow JR, Trudeau JB, Wong HP, Wu W, Kaminski N, Wenzel SE, Modena BD. BAL Cell Gene Expression in Severe Asthma Reveals Mechanisms of Severe Disease and Influences of Medications. Am J Respir Crit Care Med 2019; 200:837-856. [PMID: 31161938 PMCID: PMC6812436 DOI: 10.1164/rccm.201811-2221oc] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Accepted: 06/03/2019] [Indexed: 01/16/2023] Open
Abstract
Rationale: Gene expression of BAL cells, which samples the cellular milieu within the lower respiratory tract, has not been well studied in severe asthma.Objectives: To identify new biomolecular mechanisms underlying severe asthma by an unbiased, detailed interrogation of global gene expression.Methods: BAL cell expression was profiled in 154 asthma and control subjects. Of these participants, 100 had accompanying airway epithelial cell gene expression. BAL cell expression profiles were related to participant (age, sex, race, and medication) and sample traits (cell proportions), and then severity-related gene expression determined by correlating transcripts and coexpression networks to lung function, emergency department visits or hospitalizations in the last year, medication use, and quality-of-life scores.Measurements and Main Results: Age, sex, race, cell proportions, and medications strongly influenced BAL cell gene expression, but leading severity-related genes could be determined by carefully identifying and accounting for these influences. A BAL cell expression network enriched for cAMP signaling components most differentiated subjects with severe asthma from other subjects. Subsequently, an in vitro cellular model showed this phenomenon was likely caused by a robust upregulation in cAMP-related expression in nonsevere and β-agonist-naive subjects given a β-agonist before cell collection. Interestingly, ELISAs performed on BAL lysates showed protein levels may partly disagree with expression changes.Conclusions: Gene expression in BAL cells is influenced by factors seldomly considered. Notably, β-agonist exposure likely had a strong and immediate impact on cellular gene expression, which may not translate to important disease mechanisms or necessarily match protein levels. Leading severity-related genes were discovered in an unbiased, system-wide analysis, revealing new targets that map to asthma susceptibility loci.
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Affiliation(s)
- Nathaniel Weathington
- Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Michael E. O’Brien
- Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Josiah Radder
- Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Thomas C. Whisenant
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California
| | - Eugene R. Bleecker
- Division of Genetics, Genomics and Precision Medicine, University of Arizona, Tucson, Arizona
| | - William W. Busse
- Division of Allergy, Pulmonary, and Critical Care Medicine, University of Wisconsin, Madison, Wisconsin
| | - Serpil C. Erzurum
- Lerner Research Institute, Respiratory Institute, Cleveland Clinic, Cleveland, Ohio
| | - Benjamin Gaston
- Division of Pediatric Pulmonary, Allergy and Immunology, Case Western Reserve University and Rainbow Babies Children’s Hospital, Cleveland, Ohio
| | - Annette T. Hastie
- Section on Pulmonary, Critical Care, Allergy and Immunologic Diseases, Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Nizar N. Jarjour
- Division of Allergy, Pulmonary, and Critical Care Medicine, University of Wisconsin, Madison, Wisconsin
| | - Deborah A. Meyers
- Division of Genetics, Genomics and Precision Medicine, University of Arizona, Tucson, Arizona
| | - Jadranka Milosevic
- Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Wendy C. Moore
- Section on Pulmonary, Critical Care, Allergy and Immunologic Diseases, Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - John R. Tedrow
- Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - John B. Trudeau
- Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Hesper P. Wong
- Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Wei Wu
- Computational Biology Department, Carnegie Mellon University, Pittsburgh, Pennsylvania
| | - Naftali Kaminski
- Pulmonary, Critical Care and Sleep Medicine, Yale School of Medicine, New Haven, Connecticut
| | - Sally E. Wenzel
- Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
- Department of Environmental and Occupational Health, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania; and
| | - Brian D. Modena
- Division of Allergy, National Jewish Hospital, Denver, Colorado
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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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CCAAT/enhancer binding protein β in relation to ER stress, inflammation, and metabolic disturbances. BIOMED RESEARCH INTERNATIONAL 2015; 2015:324815. [PMID: 25699273 PMCID: PMC4324884 DOI: 10.1155/2015/324815] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 12/12/2014] [Accepted: 12/12/2014] [Indexed: 12/12/2022]
Abstract
The prevalence of the metabolic syndrome and underlying metabolic disturbances increase rapidly in developed countries. Various molecular targets are currently under investigation to unravel the molecular mechanisms that cause these disturbances. This is done in attempt to counter or prevent the negative health consequences of the metabolic disturbances. Here, we reviewed the current knowledge on the role of C/EBP-β in these metabolic disturbances. C/EBP-β deletion in mice resulted in downregulation of hepatic lipogenic genes and increased expression of β-oxidation genes in brown adipose tissue. Furthermore, C/EBP-β is important in the differentiation and maturation of adipocytes and is increased during ER stress and proinflammatory conditions. So far, studies were only conducted in animals and in cell systems. The results found that C/EBP-β is an important transcription factor within the metabolic disturbances of the metabolic system. Therefore, it is interesting to examine the potential role of C/EBP-β at molecular and physiological level in humans.
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McCarthy TL, Centrella M. Prostaglandin dependent control of an endogenous estrogen receptor agonist by osteoblasts. J Cell Physiol 2014; 230:1104-14. [PMID: 25292157 DOI: 10.1002/jcp.24842] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Accepted: 09/29/2014] [Indexed: 12/30/2022]
Abstract
Estrogen receptor (ER) activation has complex effects on bone cells, and loss of circulating estradiol adversely affects skeletal status in women. Hormone replacement therapy effectively circumvents bone loss after menopause, but enhances disease risk in other tissues. Here we show that prostaglandin E2 (PGE2) augments the activity of an osteoblast-derived selective ER modulator, ObSERM. The stimulatory effect of PGE2 is replicated in part by either the PG receptor EP3 agonist 17-phenyl trinor PGE2 or by the PG receptor FP agonist PGF2α⋅ Whereas activation of the various PG receptors induces multiple downstream signals, the response to PGE2 was mimicked by activators of protein kinase C, and suppressed by inhibition of protein kinase C but not by inhibition of protein kinase A. Moreover, inhibition of nitric oxide synthesis and activation of the PTH and Wnt pathways increases ObSERM activity. Our studies therefore reveal that ObSERM activity is controlled in distinct ways and revise our understanding of ER activation within bone by agents or events associated with PG expression. They also predict ways to sustain or improve bone formation, fracture repair, and surgical healing without adding the risk of disease in other tissues where ER activation also has important biological functions.
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Affiliation(s)
- Thomas L McCarthy
- Departments of Pathology and Surgery, Yale University School of Medicine, New Haven, Connecticut
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8
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Regulation of C/EBPβ and resulting functions in cells of the monocytic lineage. Cell Signal 2012; 24:1287-96. [DOI: 10.1016/j.cellsig.2012.02.007] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Accepted: 02/14/2012] [Indexed: 01/10/2023]
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9
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Ogata N, Shinoda Y, Wettschureck N, Offermanns S, Takeda S, Nakamura K, Segre GV, Chung UI, Kawaguchi H. G alpha(q) signal in osteoblasts is inhibitory to the osteoanabolic action of parathyroid hormone. J Biol Chem 2011; 286:13733-40. [PMID: 21345793 DOI: 10.1074/jbc.m110.200196] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
This study examined the role of the Gα(q) signal constituted by Gα(q) and Gα(11) (encoded by Gnα(q) and Gnα(11), respectively), a major intracellular pathway of parathyroid hormone (PTH), in the PTH osteoanabolic action by the gain- and loss-of-function analyses. Transgenic mice with osteoblast-specific overexpression of the constitutively active Gnα(q) gene under the control of 2.3-kb type I collagen α1 chain (Col1a1) promoter exhibited osteopenia with decreased bone formation parameters and did not respond to the daily PTH treatment. We then established osteoblast-specific Gnα(q) and Gnα(11) double-knock-out (cDKO) mice by crossing the 2.3-kb Col1a1 promoter-Cre recombinase transgenic mice and those with Gnα(q) gene flanked with loxP and global ablation of Gnα(11) (Col1a1-Cre(+/-);Gna(q)(fl/fl);Gna(11)(-/-)) and found that the cDKO and single knock-out littermates of Gnα(q) or Gnα(11) exhibited normal bone volume and turnover under physiological conditions. With a daily injection of PTH, however, the cDKO mice, but not the single knock-out mice, showed higher bone volume and turnover than the wild-type littermates. Cultures of primary osteoblasts derived from cDKO and wild-type littermates confirmed enhancement of the PTH osteoanabolic action by the Gα(q) signal deficiency in a cell-autonomous mechanism, in association with the membrane translocation of protein kinase Cδ. This enhancement was reproduced by overexpression of regulator of G protein signaling-2, a Gα(q) signal inhibitor, in osteoblastic MC3T3-E1 cells. Hence, the Gα(q) signal plays an inhibitory role in the PTH osteoanabolic action, suggesting that its suppression may lead to a novel treatment in combination with PTH against osteoporosis.
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Affiliation(s)
- Naoshi Ogata
- Department of Bone and Cartilage Regenerative Medicine, University of Tokyo, Tokyo 113-8655, Japan
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Tsuchimochi K, Otero M, Dragomir CL, Plumb DA, Zerbini LF, Libermann TA, Marcu KB, Komiya S, Ijiri K, Goldring MB. GADD45beta enhances Col10a1 transcription via the MTK1/MKK3/6/p38 axis and activation of C/EBPbeta-TAD4 in terminally differentiating chondrocytes. J Biol Chem 2010; 285:8395-407. [PMID: 20048163 DOI: 10.1074/jbc.m109.038638] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
GADD45beta (growth arrest- and DNA damage-inducible) interacts with upstream regulators of the JNK and p38 stress response kinases. Previously, we reported that the hypertrophic zone of the Gadd45beta(-/-) mouse embryonic growth plate is compressed, and expression of type X collagen (Col10a1) and matrix metalloproteinase 13 (Mmp13) genes is decreased. Herein, we report that GADD45beta enhances activity of the proximal Col10a1 promoter, which contains evolutionarily conserved AP-1, cAMP-response element, and C/EBP half-sites, in synergism with C/EBP family members, whereas the MMP13 promoter responds to GADD45beta together with AP-1, ATF, or C/EBP family members. C/EBPbeta expression also predominantly co-localizes with GADD45beta in the embryonic growth plate. Moreover, GADD45beta enhances C/EBPbeta activation via MTK1, MKK3, and MKK6, and dominant-negative p38alphaapf, but not JNKapf, disrupts the combined trans-activating effect of GADD45beta and C/EBPbeta on the Col10a1 promoter. Importantly, GADD45beta knockdown prevents p38 phosphorylation while decreasing Col10a1 mRNA levels but does not affect C/EBPbeta binding to the Col10a1 promoter in vivo, indicating that GADD45beta influences the transactivation function of DNA-bound C/EBPbeta. In support of this conclusion, we show that the evolutionarily conserved TAD4 domain of C/EBPbeta is the target of the GADD45beta-dependent signaling. Collectively, we have uncovered a novel molecular mechanism linking GADD45beta via the MTK1/MKK3/6/p38 axis to C/EBPbeta-TAD4 activation of Col10a1 transcription in terminally differentiating chondrocytes.
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Affiliation(s)
- Kaneyuki Tsuchimochi
- Laboratory for Cartilage Biology, Research Division, The Hospital for Special Surgery, Weill Cornell Medical College, New York, New York 10021, USA
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Rapamycin and the transcription factor C/EBPbeta as a switch in osteoclast differentiation: implications for lytic bone diseases. J Mol Med (Berl) 2009; 88:227-33. [PMID: 19943027 PMCID: PMC2836244 DOI: 10.1007/s00109-009-0567-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2009] [Revised: 10/23/2009] [Accepted: 11/02/2009] [Indexed: 10/24/2022]
Abstract
Lytic bone diseases and in particular osteoporosis are common age-related diseases characterized by enhanced bone fragility due to loss of bone density. Increasingly, osteoporosis poses a major global health-care problem due to the growth of the elderly population. Recently, it was found that the gene regulatory transcription factor CCAAT/enhancer binding protein beta (C/EBPbeta) is involved in bone metabolism. C/EBPbeta occurs as different protein isoforms of variable amino terminal length, and regulation of the C/EBPbeta isoform ratio balance was found to represent an important factor in osteoclast differentiation and bone homeostasis. Interestingly, adjustment of the C/EBPbeta isoform ratio by the process of translational control is downstream of the mammalian target of rapamycin kinase (mTOR), a sensor of the nutritional status and a target of immunosuppressive and anticancer drugs. The findings imply that modulating the process of translational control of C/EBPbeta isoform expression could represent a novel therapeutic approach in osteolytic bone diseases, including cancer and infection-induced bone loss.
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Meyers JA, Su DW, Lerner A. Chronic lymphocytic leukemia and B and T cells differ in their response to cyclic nucleotide phosphodiesterase inhibitors. THE JOURNAL OF IMMUNOLOGY 2009; 182:5400-11. [PMID: 19380787 DOI: 10.4049/jimmunol.0804255] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Phosphodiesterase (PDE)4 inhibitors, which activate cAMP signaling by reducing cAMP catabolism, are known to induce apoptosis in B lineage chronic lymphocytic leukemia (CLL) cells but not normal human T cells. The explanation for such differential sensitivity remains unknown. In this study, we report studies contrasting the response to PDE4 inhibitor treatment in CLL cells and normal human T and B cells. Affymetrix gene chip analysis in the three cell populations following treatment with the PDE4 inhibitor rolipram identified a set of up-regulated transcripts with unusually high fold changes in the CLL samples, several of which are likely part of compensatory negative feedback loops. The high fold changes were due to low basal transcript levels in CLL cells, suggesting that cAMP-mediated signaling may be unusually tightly regulated in this cell type. Rolipram treatment augmented cAMP levels and induced ATF-1/CREB serine 63/133 phosphorylation in both B lineage cell types but not T cells. As treatment with the broad-spectrum PDE inhibitor 3-isobutyl-1-methylxanthine induced T cell CREB phosphorylation, we tested a series of family-specific PDE inhibitors for their ability to mimic 3-isobutyl-1-methylxanthine-induced ATF-1/CREB phosphorylation. Whereas PDE3 inhibitors alone had no effect, the combination of PDE3 and PDE4 inhibitors induced ATF-1/CREB serine 63/133 phosphorylation in T cells. Consistent with this observation, PDE3B transcript and protein levels were low in CLL cells but easily detectable in T cells. Combined PDE3/4 inhibition did not induce T cell apoptosis, suggesting that cAMP-mediated signal transduction that leads to robust ATF-1/CREB serine 63/133 phosphorylation is not sufficient to induce apoptosis in this lymphoid lineage.
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Affiliation(s)
- John A Meyers
- Evans Department of Medicine, Section of Hematology and Oncology, Boston Medical Center, Boston, MA 02118, USA
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Kim KS, Kim GS, Hwang JY, Lee HJ, Park MH, Kim KJ, Jung J, Cha HS, Shin HD, Kang JH, Park EK, Kim TH, Hong JM, Koh JM, Oh B, Kimm K, Kim SY, Lee JY. Single nucleotide polymorphisms in bone turnover-related genes in Koreans: ethnic differences in linkage disequilibrium and haplotype. BMC MEDICAL GENETICS 2007; 8:70. [PMID: 18036257 PMCID: PMC2222243 DOI: 10.1186/1471-2350-8-70] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2006] [Accepted: 11/26/2007] [Indexed: 12/20/2022]
Abstract
Background Osteoporosis is defined as the loss of bone mineral density that leads to bone fragility with aging. Population-based case-control studies have identified polymorphisms in many candidate genes that have been associated with bone mass maintenance or osteoporotic fracture. To investigate single nucleotide polymorphisms (SNPs) that are associated with osteoporosis, we examined the genetic variation among Koreans by analyzing 81 genes according to their function in bone formation and resorption during bone remodeling. Methods We resequenced all the exons, splice junctions and promoter regions of candidate osteoporosis genes using 24 unrelated Korean individuals. Using the common SNPs from our study and the HapMap database, a statistical analysis of deviation in heterozygosity depicted. Results We identified 942 variants, including 888 SNPs, 43 insertion/deletion polymorphisms, and 11 microsatellite markers. Of the SNPs, 557 (63%) had been previously identified and 331 (37%) were newly discovered in the Korean population. When compared SNPs in the Korean population with those in HapMap database, 1% (or less) of SNPs in the Japanese and Chinese subpopulations and 20% of those in Caucasian and African subpopulations were significantly differentiated from the Hardy-Weinberg expectations. In addition, an analysis of the genetic diversity showed that there were no significant differences among Korean, Han Chinese and Japanese populations, but African and Caucasian populations were significantly differentiated in selected genes. Nevertheless, in the detailed analysis of genetic properties, the LD and Haplotype block patterns among the five sub-populations were substantially different from one another. Conclusion Through the resequencing of 81 osteoporosis candidate genes, 118 unknown SNPs with a minor allele frequency (MAF) > 0.05 were discovered in the Korean population. In addition, using the common SNPs between our study and HapMap, an analysis of genetic diversity and deviation in heterozygosity was performed and the polymorphisms of the above genes among the five populations were substantially differentiated from one another. Further studies of osteoporosis could utilize the polymorphisms identified in our data since they may have important implications for the selection of highly informative SNPs for future association studies.
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Affiliation(s)
- Kyung-Seon Kim
- Center for Genome Science, National Institute of Health, 5 Nokbun-dong, Eunpyung-gu, Seoul 122-701, Republic of Korea.
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McCarthy TL, Hochberg RB, Labaree DC, Centrella M. 3-ketosteroid reductase activity and expression by fetal rat osteoblasts. J Biol Chem 2007; 282:34003-12. [PMID: 17905737 DOI: 10.1074/jbc.m707502200] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In addition to reproductive tissue, sex hormones induce transcriptional events in many connective tissue cells, including osteoblasts. Some sex hormone receptor modulators with bone sparing effects selectively target estrogen or androgen receptors, whereas others appear more promiscuous, in part through enzymatic metabolism. Rat osteoblasts express significant oxidative 3alpha-hydroxysteroid dehydrogenase activity, which can convert precursor substrates to potent androgen receptor agonists. Here we show that they also express 3-ketosteroid reductase activity, exemplified by 7-methyl-17-ethynyl-19-norandrostan-5 (10)en-3-one (tibolone) conversion to potent estrogen receptor alpha agonists. Conversion was rapid and quantitative, with 3alpha-hydroxytibolone as the primary metabolite. Consistently, tibolone induced estrogen receptor alpha-dependent gene promoter activity through cis-acting estrogen response elements, increased the stimulatory effect of TGF-beta on Smad-dependent gene promoter activity, and enhanced prostaglandin E2-induced activity of transcription factor Runx2. Rat osteoblasts express the 3-ketosteroid reductase AKR1C9, an aldo-keto reductase gene family member. Exposure to prostaglandin E2 increased AKR1C9 gene promoter activity and mRNA expression. AKR1C9 promoter activity was also enhanced by overexpression of protein kinase A catalytic subunit or transcription factor C/EBPdelta, and the effect of PGE2 was reduced by dominant negative C/EBPdelta competition or C/EBPdelta antisense expression. Moreover, prostaglandin E2 increased the amount of functional endogenous nuclear C/EBPdelta that could bind specifically to a distinct domain approximately 1.8-kb upstream from the start site of AKR1C9 transcription. In summary, in addition to 3alpha-hydroxysteroid dehydrogenase, rat osteoblasts express significant and regulatable 3-ketosteroid reductase activity. Through these enzymes, they may selectively metabolize precursor compounds into potent steroid receptor agonists locally within bone.
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Affiliation(s)
- Thomas L McCarthy
- Department of Surgery, Section of Plastic Surgery, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA.
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McCarthy TL, Pham TH, Knoll BI, Centrella M. Prostaglandin E2 increases transforming growth factor-beta type III receptor expression through CCAAT enhancer-binding protein delta in osteoblasts. Mol Endocrinol 2007; 21:2713-24. [PMID: 17636036 DOI: 10.1210/me.2007-0210] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Variations in individual TGF-beta receptors (TbetaRs) may modify TGF-beta activity and significantly alter its effects on connective tissue growth or repair. Differences in the amount of TbetaR type III (TbetaRIII) relative to signal transducing TbetaRI occur on bone cells during differentiation or in response to other growth regulators. Here we investigated prostaglandin (PG) E2, a potent effector during trauma, inflammation, or mechanical load, on TbetaR expression in primary osteoblast-enriched cultures. PGE2 rapidly increased TbetaRIII mRNA and protein expression and enhanced TbetaRIII gene promoter activity through a discrete region within 0.4 kb of the transcription start site. PGE2 alters osteoblast function through multiple signal-inducing pathways. In this regard, protein kinase A (PKA) activators, PGE1 and forskolin, also enhanced gene expression through the TbetaRIII gene promoter, whereas protein kinase C activators, PGF2alpha and phorbol myristate acetate, did not. The stimulatory effect of PGE2 on TbetaRIII promoter activity was suppressed by a dominant negative PKA-regulatory subunit, but not by dominant negative protein kinase C. PGE2 specifically increased nuclear factor CCAAT enhancer-binding protein delta (C/EBPdelta) binding to a half-binding site upstream of the basal TbetaRIII promoter region, and promoter activity was sensitive to C/EBPdelta overexpression and to dominant-negative C/EBPdelta competition. In parallel with their effect on TbetaRIII expression, activators of PKA decreased TGF-beta-induced activity. In summary, high levels of PGE2 that occur with inflammation or trauma may, through PKA-activated C/EBPdelta, preferentially increase TbetaRIII expression and in this way delay TGF-beta-dependent activation of osteoblasts during the early stabilization phase of bone repair.
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Affiliation(s)
- Thomas L McCarthy
- Department of Surgery and Section of Plastic Surgery, Yale University School of Medicine, New Haven, Connecticut 06520, USA.
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Yamaguchi M, Ogata N, Shinoda Y, Akune T, Kamekura S, Terauchi Y, Kadowaki T, Hoshi K, Chung UI, Nakamura K, Kawaguchi H. Insulin receptor substrate-1 is required for bone anabolic function of parathyroid hormone in mice. Endocrinology 2005; 146:2620-8. [PMID: 15718274 DOI: 10.1210/en.2004-1511] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Bone anabolic action of PTH has been suggested to be mediated by induction of IGF-I in osteoblasts; however, little is known about the molecular mechanism by which IGF-I leads to bone formation under the PTH stimulation. This study initially confirmed in mouse osteoblast cultures that PTH treatment increased IGF-I mRNA and protein levels and alkaline phosphatase activity, which were accompanied by phosphorylations of IGF-I receptor, insulin receptor substrate (IRS)-1 and IRS-2, essential adaptor molecules for the IGF-I signaling. To learn the involvement of IRS-1 and IRS-2 in the bone anabolic action of PTH in vivo, IRS-1-/- and IRS-2-/- mice and their respective wild-type littermates were given daily injections of PTH (80 mug/kg) or vehicle for 4 wk. In the wild-type mice, the PTH injection increased bone mineral densities of the femur, tibia, and vertebrae by 10-20% without altering the serum IGF-I level. These stimulations were similarly seen in IRS-2-/- mice; however, they were markedly suppressed in IRS-1-/- mice. Although the PTH anabolic effects were stronger on trabecular bones than on cortical bones, the stimulations on both bones were blocked in IRS-1-/- mice but not in IRS-2-/- mice. Histomorphometric and biochemical analyses showed an increased bone turnover by PTH, which was also blunted by the IRS-1 deficiency, though not by the IRS-2 deficiency. These results indicate that the PTH bone anabolic action is mediated by the activation of IRS-1, but not IRS-2, as a downstream signaling of IGF-I that acts locally as an autocrine/paracrine factor.
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Affiliation(s)
- Masayuki Yamaguchi
- Department of Sensory and Motor System Medicine, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-8655, Japan
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