101
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Hiragun T, Peng Z, Beaven MA. Dexamethasone up-regulates the inhibitory adaptor protein Dok-1 and suppresses downstream activation of the mitogen-activated protein kinase pathway in antigen-stimulated RBL-2H3 mast cells. Mol Pharmacol 2004; 67:598-603. [PMID: 15608142 DOI: 10.1124/mol.104.008607] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The glucocorticoid dexamethasone suppresses antigen-induced degranulation, cytokine production, and intermediate signaling events in RBL-2H3 mast cells, although the exact mechanisms are uncertain. By microarray analysis, we discovered that expression of the inhibitory adaptor protein, downstream of tyrosine kinase (Dok)-1, was up-regulated 4-fold in dexamethasone-treated RBL-2H3 cells. The up-regulation was apparent with as little as 1 to 10 nM dexamethasone. Treatment with dexamethasone also enhanced tyrosine phosphorylation of Dok-1, augmented recruitment of Ras GTPase-activating protein (RasGAP) by Dok-1, and inhibited activation of the mitogen-activated protein (MAP) kinase pathway in antigen-stimulated cells. The same effects were obtained by transient overexpression of Dok-1 but not by overexpression of Dok-1 that was mutated in RasGAP-binding domain. The negative regulatory role of Dok-1 was further validated by the expression of small interfering RNA directed against Dok-1, which enhanced activation of MAP kinase and subsequent release of arachidonic acid and tumor necrosis factor-alpha. These findings identify Dok-1 as mediator of the antiallergic actions of dexamethasone and as a negative regulator of the MAP kinase pathway and downstream release of inflammatory mediators.
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Affiliation(s)
- Takaaki Hiragun
- Laboratory of Molecular Immunology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892-1760, USA
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102
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Wu W, Pew T, Zou M, Pang D, Conzen SD. Glucocorticoid receptor-induced MAPK phosphatase-1 (MPK-1) expression inhibits paclitaxel-associated MAPK activation and contributes to breast cancer cell survival. J Biol Chem 2004; 280:4117-24. [PMID: 15590693 DOI: 10.1074/jbc.m411200200] [Citation(s) in RCA: 138] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Glucocorticoid receptor (GR) activation has recently been shown to inhibit apoptosis in breast epithelial cells. We have previously described a group of genes that is rapidly up-regulated in these cells following dexamethasone (Dex) treatment. In an effort to dissect the mechanisms of GR-mediated breast epithelial cell survival, we now examine the molecular events downstream of GR activation. Here we show that GR activation leads to both the rapid induction of MAPK phosphatase-1 (MKP-1) mRNA and its sustained expression. Induction of the MKP-1 protein in the MCF10A-Myc and MDA-MB-231 breast epithelial cell lines was also seen. Paclitaxel treatment resulted in MAPK activation and apoptosis of MDA-MB-231 breast cancer cells, and both processes were inhibited by Dex pretreatment. Furthermore, induction of MKP-1 correlated with the inhibition of extracellular signal-regulated kinase (ERK1/2) and c-Jun N-terminal kinase (JNK) activity, whereas p38 activity was minimally affected. Blocking Dex-induced MKP-1 induction using small interfering RNA increased ERK1/2 and JNK phosphorylation and decreased cell survival. ERK1/2 and JNK inactivation was associated with Ets-like transcription factor-1 (ELK-1) dephosphorylation. To explore the gene expression changes that occur downstream of ELK-1 dephosphorylation, we used a combination of temporal gene expression data and promoter element analyses. This approach revealed a previously unrecognized transcriptional target of ELK-1, the human tissue plasminogen activator (tPA). We verified the predicted ELK-1--> tPA transcriptional regulatory relationship using a luciferase reporter assay. We conclude that GR-mediated MAPK inactivation contributes to cell survival and that the potential transcriptional targets of this inhibition can be identified from large scale gene array analysis.
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MESH Headings
- Amino Acid Motifs
- Antineoplastic Agents, Phytogenic/pharmacology
- Apoptosis
- Blotting, Northern
- Blotting, Western
- Breast/metabolism
- Cell Cycle Proteins/metabolism
- Cell Cycle Proteins/physiology
- Cell Line, Tumor
- Cell Survival
- DNA-Binding Proteins/biosynthesis
- Down-Regulation
- Dual Specificity Phosphatase 1
- Enzyme Activation
- Gene Expression Regulation, Neoplastic
- Genes, Reporter
- Humans
- Immediate-Early Proteins/metabolism
- Immediate-Early Proteins/physiology
- JNK Mitogen-Activated Protein Kinases/biosynthesis
- JNK Mitogen-Activated Protein Kinases/metabolism
- Luciferases/metabolism
- MAP Kinase Kinase 4
- MAP Kinase Signaling System
- Mitogen-Activated Protein Kinase 1/biosynthesis
- Mitogen-Activated Protein Kinase 3/biosynthesis
- Mitogen-Activated Protein Kinase Kinases/metabolism
- Mitogen-Activated Protein Kinases/metabolism
- Models, Biological
- Oligonucleotide Array Sequence Analysis
- Paclitaxel/pharmacology
- Phosphoprotein Phosphatases/metabolism
- Phosphoprotein Phosphatases/physiology
- Phosphorylation
- Protein Binding
- Protein Phosphatase 1
- Protein Tyrosine Phosphatases/metabolism
- Protein Tyrosine Phosphatases/physiology
- Proto-Oncogene Proteins/biosynthesis
- RNA, Messenger/metabolism
- RNA, Small Interfering/metabolism
- Receptors, Glucocorticoid/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Time Factors
- Tissue Plasminogen Activator/metabolism
- Transcription Factors/biosynthesis
- Transcription, Genetic
- Transfection
- ets-Domain Protein Elk-1
- p38 Mitogen-Activated Protein Kinases/metabolism
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Affiliation(s)
- Wei Wu
- Department of Medicine and the Committee on Cancer Biology, University of Chicago, Chicago, Illinois 60637, USA
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103
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Toh ML, Yang Y, Leech M, Santos L, Morand EF. Expression of mitogen-activated protein kinase phosphatase 1, a negative regulator of the mitogen-activated protein kinases, in rheumatoid arthritis: up-regulation by interleukin-1beta and glucocorticoids. ACTA ACUST UNITED AC 2004; 50:3118-28. [PMID: 15476200 DOI: 10.1002/art.20580] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
OBJECTIVE Mitogen-activated protein kinases (MAPKs) are activated by proinflammatory stimuli. MAPK phosphatases (MKPs), in particular MKP-1, have been identified as endogenous negative regulators of MAPK activation. Since MAPKs are known to be important in rheumatoid arthritis (RA) synoviocyte activation, this study assessed the expression, regulation, and function of MKP-1 in RA. METHODS MKP-1 expression was measured by Western blotting (WB) and real-time polymerase chain reaction (PCR). RA fibroblast-like synoviocytes (FLS) were treated with interleukin-1beta (IL-1beta), tumor necrosis factor alpha, fetal calf serum, and dexamethasone. Expression of MAPKs in RA FLS was analyzed by WB using phosphospecific antibodies, while IL-6 expression was assessed by real-time PCR. RESULTS MKP-1 protein and messenger RNA were detected in cultured RA FLS. IL-1beta rapidly up-regulated MKP-1, coinciding with reciprocal down-regulation of ERK, JNK, and p38 MAPK phosphorylation. Dexamethasone rapidly and sustainably up-regulated MKP-1, and this also coincided with down-regulation of ERK, JNK, and p38 MAPK phosphorylation. In addition, dexamethasone augmented IL-1beta-induced up-regulation of MKP-1, and this was associated with inhibition of ERK, JNK, and p38 MAPK phosphorylation and IL-6 expression. Dexamethasone had no effect on the phosphorylation of upstream kinases such as MEKK-3/6. In the presence of glucocorticoid (GC) receptor antagonist RU 486, the dexamethasone-mediated up-regulation of MKP-1 was impaired. Moreover, inhibition of MKP-1 expression impaired dexamethasone-mediated inhibition of MAPK phosphorylation. CONCLUSION This study demonstrates the expression of MKP-1 in RA FLS. Cytokine and GC regulation of MKP-1 may be important in determining the magnitude of the inflammatory response in RA that is mediated via MAPKs. The effects of GCs in RA may be mediated, in part, via GC receptor-dependent up-regulation of MKP-1.
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Affiliation(s)
- Myew-Ling Toh
- Monash Medical Centre, Clayton, Melbourne, Australia
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104
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Kim JB, Ju JY, Kim JH, Kim TY, Yang BH, Lee YS, Son H. Dexamethasone inhibits proliferation of adult hippocampal neurogenesis in vivo and in vitro. Brain Res 2004; 1027:1-10. [PMID: 15494151 DOI: 10.1016/j.brainres.2004.07.093] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/28/2004] [Indexed: 11/19/2022]
Abstract
Activation of glucocorticoid receptor (GR) induces a reduction of adult hippocampal neurogenesis found in dentate gyrus (DG). However, the nature of specific effects by glucocorticoid in hippocampal neurogenesis is not known. In this report, we show differential effects of dexamethasone (DEX), a glucocorticoid receptor agonist, on proliferation and functional differentiation of adult hippocampal progenitor cells in DG. Two-month-old adult rats received daily injections of DEX for 9 days and were sacrificed 12 h and 28 days after the ninth injection. Proliferation assays showed that DEX inhibited proliferation of neural progenitor cells and the inhibitory effects of DEX was not detected 28 days after recovery. Functional differentiation studies using B-cell lymphoma protein-2 (Bcl-2), brain-derived neurotrophic factor (BDNF), p-ERK, and neuronal nuclear protein (NeuN) antibodies revealed that the expressions of Bcl-2 and BDNF were not significantly different between control and DEX-treated rats. In contrast, however, the activation of extracellular signal-regulated kinase (ERK) was downregulated 12 h, but not 28 days, after the DEX treatment. When adult hippocampal progenitor cell cultures were treated with subchronic DEX, proliferation of the progenitor cells was suppressed. Taken these in vitro and in vivo results together, it is concluded that glucocorticoid receptor activation blocks only proliferation, but not differentiation, in hippocampal neurogenesis.
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Affiliation(s)
- Jong Bin Kim
- Department of Biochemistry, Hanyang University College of Medicine, 17 Haengdang-dong, Sungdong-gu, Seoul 133-791, Republic of Korea
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105
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Qin L, Li X, Ko JK, Partridge NC. Parathyroid hormone uses multiple mechanisms to arrest the cell cycle progression of osteoblastic cells from G1 to S phase. J Biol Chem 2004; 280:3104-11. [PMID: 15513917 DOI: 10.1074/jbc.m409846200] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Parathyroid hormone (PTH) plays a major role in bone remodeling and has the ability to increase bone mass if administered daily. In vitro, PTH inhibits the growth of osteoblastic cell lines, arresting them in G(1) phase. Here, we demonstrate that PTH regulates the expression of at least three genes to achieve the following: inducing expression of MAPK phosphatase 1 (MKP-1) and p21(Cip1) and decreasing expression of cyclin D1 at both mRNA and protein levels. The induction of MKP-1 causes the dephosphorylation of extracellular signal-regulated kinase and therefore the decrease in cyclin D1. Overexpression of MKP-1 arrests UMR cells in G(1) phase. The mechanisms involved in PTH regulation of these genes were studied. Most importantly, PTH administration produces similar effects on expression of these genes in rat femoral metaphyseal primary spongiosa. Analyses of p21(Cip1) expression levels in bone indicate that repeated daily PTH injections make the osteoblast more sensitive to successive PTH treatments, and this might be an important feature for the anabolic functions of PTH. In summary, our data suggest that one mechanism for PTH to exert its anabolic effect is to arrest the cell cycle progression of the osteoblast and hence increase its differentiation.
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Affiliation(s)
- Ling Qin
- Department of Physiology and Biophysics, UMDNJ-Robert Wood Johnson Medical School, Piscataway, New Jersey 08854, USA
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106
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Muscella A, Greco S, Elia MG, Storelli C, Marsigliante S. Differential signalling of purinoceptors in HeLa cells through the extracellular signal-regulated kinase and protein kinase C pathways. J Cell Physiol 2004; 200:428-39. [PMID: 15254971 DOI: 10.1002/jcp.20033] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
We have previously shown that HeLa cells express P2Y2 and P2Y6 receptors endogenously and determined the pathways by which the P2Y2 controls proliferation and Na+/K+ATPase activity. Our objective in this study was to investigate the hypothesis that P2Y6 also controls proliferation and Na+/K+ATPase activity; the pathways used in these actions were partially characterised. We found that P2Y6 activation controlled cell proliferation but not the activity of the Na+/K+ATPase. UDP activation of P2Y6 provoked: (a) an increase in free cytosolic calcium; (b) the activation of protein kinase C-alpha, -beta, -delta, -epsilon, and -zeta but not of PKC-iota and -eta; (c) the phosphorylation of the extracellular signal-regulated protein kinases 1 and 2 (ERK1/2); (d) the expression of c-Fos protein. The P2Y6 induced cell proliferation was blocked by the mitogen-activated protein kinase kinase (MAPKK) inhibitor PD098059, thereby indicating that the ERK pathway mediates the mitogenic signalling of P2Y6. PKC and phosphoinositide 3-kinase (PI3K) inhibitors were tested at two different time points of ERK1/2 phosphorylation (10 and 60 min). The results suggest that novel PKCs and PI3K initiate the response but both conventional and atypical PKCs are required for the maintenance of the UDP-induced phosphorylation of ERK1/2. The induction of c-Fos was greatly diminished by conventional or atypical PKC-zeta inhibition, suggesting that it may be due to PKC-alpha/beta and -zeta activity. These observations demonstrate that UDP acts as a proliferative agent in HeLa cells activating multiple signalling pathways involving conventional, novel, and atypical PKCs, PI3K, and ERK. Of these pathways, conventional and atypical PKCs appear responsible for the induction of c-Fos, while ERK is responsible for cell proliferation and depends upon both novel and atypical PKCs and PI3K activities.
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Affiliation(s)
- Antonella Muscella
- Laboratorio di Fisiologia Cellulare, Dipartimento di Scienze e Tecnologie Biologiche e Ambientali, Università di Lecce, Ecotekne, Lecce, Italia
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107
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Cooper MS. Sensitivity of bone to glucocorticoids. Clin Sci (Lond) 2004; 107:111-23. [PMID: 15113280 DOI: 10.1042/cs20040070] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2004] [Revised: 04/14/2004] [Accepted: 04/28/2004] [Indexed: 11/17/2022]
Abstract
Glucocorticoids are used widely in a range of medical specialities, but their main limitation is an adverse impact on bone. Although physicians are increasingly aware of these deleterious effects, the marked variation in susceptibility between individuals makes it difficult to predict who will develop skeletal complications with these drugs. Although the mechanisms underlying the adverse effects on bone remain unclear, the most important effect appears to be a rapid and substantial decrease in bone formation. This review will examine recent studies that quantify the risk of fracture with glucocorticoids, the mechanisms that underlie this increase in risk and the potential basis for differences in individual sensitivity. An important determinant of glucocorticoid sensitivity appears to be the presence of glucocorticoid-metabolizing enzymes within osteoblasts and this may enable improved estimates of risk and generate new approaches to the development of bone-sparing anti-inflammatory drugs.
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Affiliation(s)
- Mark S Cooper
- Division of Medical Sciences, University of Birmingham, Queen Elizabeth Hospital, Edgbaston, Birmingham B15 2TH, UK.
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108
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Sakai A, Han J, Cato ACB, Akira S, Li JD. Glucocorticoids synergize with IL-1beta to induce TLR2 expression via MAP Kinase Phosphatase-1-dependent dual Inhibition of MAPK JNK and p38 in epithelial cells. BMC Mol Biol 2004; 5:2. [PMID: 15125785 PMCID: PMC419700 DOI: 10.1186/1471-2199-5-2] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2003] [Accepted: 05/04/2004] [Indexed: 11/16/2022] Open
Abstract
Background Despite the importance of glucocorticoids in suppressing immune and inflammatory responses, their role in enhancing host immune and defense response against invading bacteria is poorly understood. Toll-like receptor 2 (TLR2) has recently gained importance as one of the major host defense receptors. The increased expression of TLR2 in response to bacteria-induced cytokines has been thought to be crucial for the accelerated immune response and resensitization of epithelial cells to invading pathogens. Results We show that IL-1β, a key proinflammatory cytokine, greatly up-regulates TLR2 expression in human epithelial cells via a positive IKKβ-IκBα-dependent NF-κB pathway and negative MEKK1-MKK4/7-JNK1/2 and MKK3/6-p38 α/β pathways. Glucocorticoids synergistically enhance IL-1β-induced TLR2 expression via specific up-regulation of the MAP kinase phosphatase-1 that, in turn, leads to dephosphorylation and inactivation of both MAPK JNK and p38, the negative regulators for TLR2 induction. Conclusion These results indicate that glucocorticoids not only suppress immune and inflammatory response, but also enhance the expression of the host defense receptor, TLR2. Thus, our studies may bring new insights into the novel role of glucocorticoids in orchestrating and optimizing host immune and defense responses during bacterial infections and enhance our understanding of the signaling mechanisms underlying the glucocorticoid-mediated attenuation of MAPK.
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Affiliation(s)
- Akihiro Sakai
- Gonda Department of Cell and Molecular Biology, House Ear Institute, and the Department of Otolaryngology, University of Southern California, Los Angeles, CA 90057, USA
| | - Jiahuai Han
- Department of Immunology, the Scripps Research Institute, La Jolla, CA 92037, USA
| | - Andrew CB Cato
- Forschungszentrum Karlsruhe, Institute of Toxicology & Genetics, P.O. Box 3640, D-76021 Karlsruhe, Germany
| | - Shizuo Akira
- Department of Host Defense, Research Institute for Microbial Diseases, Osaka University, CREST of Japan Science and Technology Corporation, 3-1 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Jian-Dong Li
- Gonda Department of Cell and Molecular Biology, House Ear Institute, and the Department of Otolaryngology, University of Southern California, Los Angeles, CA 90057, USA
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109
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Hulley P, Davison A. Regulation of tyrosine phosphorylation cascades by phosphatases: What the actions of vanadium teach us. ACTA ACUST UNITED AC 2003. [DOI: 10.1002/jtra.10040] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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110
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Jeong HJ, Na HJ, Hong SH, Kim HM. Inhibition of the stem cell factor-induced migration of mast cells by dexamethasone. Endocrinology 2003; 144:4080-6. [PMID: 12933682 DOI: 10.1210/en.2003-0115] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Mast cell accumulation can be causally related to several allergic inflammations. Previous work has demonstrated that glucocorticoids decreased tissue mast cell number, and stem cell factor (SCF)-induced migration of mast cells required p38 MAPK activation. In the present study we investigated the effects of dexamethasone on SCF-induced migration of rat peritoneal mast cells (RPMCs). SCF significantly induced the migration of RPMCs at 4 h. Dexamethasone dose-dependently inhibited SCF-induced migration of RPMCs (approximately 90.1% at 100 nM; P < 0.05). The MAPK p38 inhibitor SB203580 (20 microM) also inhibited the SCF-induced migration. The ability of SCF to enhance morphological alteration and filamentous actin formation was also abolished by treatment with dexamethasone. Dexamethasone inhibited SCF-induced p38 MAPK activation to near-basal levels and induced MAPK phosphatase-1 expression. In addition, SCF-induced inflammatory cytokine production was significantly inhibited by treatment with dexamethasone or SB203580 (P < 0.01). Our results show that dexamethasone potently regulates SCF-induced migration, p38 MAPK activation, and inflammatory cytokine production through the expression of MKP-1 protein in RPMCs. Such modulation may have functional consequences during dexamethasone treatment, especially mast cell-mediated allergic inflammation disorders.
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Affiliation(s)
- Hyun-Ja Jeong
- Department of Pharmacology, Kyung Hee University College of Oriental Medicine, 130-701 Seoul, South Korea
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111
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De Bosscher K, Vanden Berghe W, Haegeman G. The interplay between the glucocorticoid receptor and nuclear factor-kappaB or activator protein-1: molecular mechanisms for gene repression. Endocr Rev 2003; 24:488-522. [PMID: 12920152 DOI: 10.1210/er.2002-0006] [Citation(s) in RCA: 621] [Impact Index Per Article: 29.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The inflammatory response is a highly regulated physiological process that is critically important for homeostasis. A precise physiological control of inflammation allows a timely reaction to invading pathogens or to other insults without causing overreaction liable to damage the host. The cellular signaling pathways identified as important regulators of inflammation are the signal transduction cascades mediated by the nuclear factor-kappaB and the activator protein-1, which can both be modulated by glucocorticoids. Their use in the clinic includes treatment of rheumatoid arthritis, asthma, allograft rejection, and allergic skin diseases. Although glucocorticoids have been widely used since the late 1940s, the molecular mechanisms responsible for their antiinflammatory activity are still under investigation. The various molecular pathways proposed so far are discussed in more detail.
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Affiliation(s)
- Karolien De Bosscher
- Department of Molecular Biology, Ghent University, K. L. Ledeganckstraat 35, 9000 Gent, Belgium
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112
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Clark AR, Dean JLE, Saklatvala J. Post-transcriptional regulation of gene expression by mitogen-activated protein kinase p38. FEBS Lett 2003; 546:37-44. [PMID: 12829234 DOI: 10.1016/s0014-5793(03)00439-3] [Citation(s) in RCA: 161] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The mitogen-activated protein kinase p38 pathway was originally identified as a signalling cascade activated by pro-inflammatory stimuli and cellular stresses, and playing a critical role in the translational regulation of pro-inflammatory cytokine synthesis. In almost a decade since this discovery, a great deal has been learned about the role of the p38 pathway in the post-transcriptional regulation of pro-inflammatory gene expression. However, important questions remain to be answered concerning the specificity and mechanism or mechanisms of action of p38. This review describes recent progress and remaining puzzles in the field of post-transcriptional regulation by p38.
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Affiliation(s)
- Andrew R Clark
- Kennedy Institute of Rheumatology Division, Faculty of Medicine, Imperial College London, 1 Aspenlea Road, Hammersmith, London W6 8LH, UK.
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