Tumor necrosis factor-α upregulates 11β-hydroxysteroid dehydrogenase type 1 expression by CCAAT/enhancer binding protein-β in HepG2 cells

2009 ◽  
Vol 296 (2) ◽  
pp. E367-E377 ◽  
Author(s):  
Irena D. Ignatova ◽  
Radina M. Kostadinova ◽  
Christopher E. Goldring ◽  
Andrea R. Nawrocki ◽  
Felix J. Frey ◽  
...  
Keyword(s):  
P38 Mapk ◽  
Hepg2 Cells ◽  
Binding Protein ◽  
Hydroxysteroid Dehydrogenase ◽  
Expression Vectors ◽  
Enhancer Binding Protein ◽  
Tnf Α ◽  
Ccaat Enhancer Binding Protein

The enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) catalyzes the conversion of inactive to active glucocorticoids. 11β-HSD1 plays a crucial role in the pathogenesis of obesity and controls glucocorticoid actions in inflammation. Several studies have demonstrated that TNF-α increases 11β-HSD1 mRNA and activity in various cell models. Here, we demonstrate that mRNA and activity of 11β-HSD1 is increased in liver tissue from transgenic mice overexpressing TNF-α, indicating that this effect also occurs in vivo. To dissect the molecular mechanism of this increase, we investigated basal and TNF-α-induced transcription of the 11β-HSD1 gene ( HSD11B1) in HepG2 cells. We found that TNF-α acts via p38 MAPK pathway. Transient transfections with variable lengths of human HSD11B1 promoter revealed highest activity with or without TNF-α in the proximal promoter region (−180 to +74). Cotransfection with human CCAAT/enhancer binding protein-α (C/EBPα) and C/EBPβ-LAP expression vectors activated the HSD11B1 promoter with the strongest effect within the same region. Gel shift and RNA interference assays revealed the involvement of mainly C/EBPα, but also C/EBPβ, in basal and only of C/EBPβ in the TNF-α-induced HSD11B1 expression. Chromatin immunoprecipitation assay confirmed in vivo the increased abundance of C/EBPβ on the proximal HSD11B1 promoter upon TNF-α treatment. In conclusion, C/EBPα and C/EBPβ control basal transcription, and TNF-α upregulates 11β-HSD1, most likely by p38 MAPK-mediated increased binding of C/EBPβ to the human HSD11B1 promoter. To our knowledge, this is the first study showing involvement of p38 MAPK in the TNF-α-mediated 11β-HSD1 regulation, and that TNF-α stimulates enzyme activity in vivo.

scholarly journals Regulation of Adipocyte 11β-Hydroxysteroid Dehydrogenase Type 1 (11β-HSD1) by CCAAT/Enhancer-Binding Protein (C/EBP) β Isoforms, LIP and LAP

PLoS ONE ◽  
2012 ◽  
Vol 7 (5) ◽  
pp. e37953 ◽  
Author(s):  
Cristina L. Esteves ◽  
Val Kelly ◽  
Valérie Bégay ◽  
Tak Y. Man ◽  
Nicholas M. Morton ◽  
...  
Keyword(s):  
Protein C ◽  
Binding Protein ◽  
Hydroxysteroid Dehydrogenase ◽  
Enhancer Binding Protein ◽  
Ccaat Enhancer Binding Protein

CCAAT/enhancer binding protein positively regulates the rat 11β-hydroxysteroid dehydrogenase type 1 promoter in liver cells

1997 ◽  
Vol 25 (2) ◽  
pp. 235S-235S ◽  
Author(s):  
LOUISE J. S. WILLIAMS ◽  
VAL LYONS ◽  
RUTH WALLACE ◽  
JONATHAN R. SECKL ◽  
KAREN E. CHAPMAN
Keyword(s):  
Binding Protein ◽  
Hydroxysteroid Dehydrogenase ◽  
Liver Cells ◽  
Enhancer Binding Protein ◽  
Ccaat Enhancer Binding Protein

scholarly journals Glucocorticoid Regulation of the Promoter of 11β-Hydroxysteroid Dehydrogenase Type 1 Is Indirect and Requires CCAAT/Enhancer-Binding Protein-β

2008 ◽  
Vol 22 (9) ◽  
pp. 2049-2060 ◽  
Author(s):  
Shuji Sai ◽  
Cristina L. Esteves ◽  
Val Kelly ◽  
Zoi Michailidou ◽  
Karen Anderson ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Binding Protein ◽  
A549 Cells ◽  
Hydroxysteroid Dehydrogenase ◽  
Glucocorticoid Treatment ◽  
Enhancer Binding Protein ◽  
Ccaat Enhancer Binding Protein ◽  
Glucocorticoid Induction ◽  
Glucocorticoid Action

Abstract 11β-Hydroxysteroid dehydrogenase type 1 (11β-HSD1) converts inert 11keto-glucocorticoids to active 11β-hydroxy forms, thereby amplifying intracellular glucocorticoid action. Up-regulation of 11β-HSD1 in adipose tissue and liver is of pathogenic importance in metabolic syndrome. However, the mechanisms controlling 11β-HSD1 transcription are poorly understood. Glucocorticoids themselves potently increase 11β-HSD1 expression in many cells, providing a potential feed-forward system to pathology. We have investigated the molecular mechanisms by which glucocorticoids regulate transcription of 11β-HSD1, exploiting an A549 cell model system in which endogenous 11β-HSD1 is expressed and is induced by dexamethasone. We show that glucocorticoid induction of 11β-HSD1 is indirect and requires new protein synthesis. A glucocorticoid-responsive region maps to between −196 and −88 with respect to the transcription start site. This region contains two binding sites for CCAAT/enhancer-binding protein (C/EBP) that together are essential for the glucocorticoid response and that bind predominantly C/EBPβ, with C/EBPδ present in a minority of the complexes. Both C/EBPβ and C/EBPδ are rapidly induced by glucocorticoids in A549 cells, but small interfering RNA-mediated knockdown shows that only C/EBPβ reduction attenuates the glucocorticoid induction of 11β-HSD1. Chromatin immunoprecipitation studies demonstrated increased binding of C/EBPβ to the 11β-HSD1 promoter in A549 cells after glucocorticoid treatment. A similar mechanism may apply in adipose tissue in vivo where increased C/EBPβ mRNA levels after glucocorticoid treatment were associated with increased 11β-HSD1 expression. C/EBPβ is a key mediator of metabolic and inflammatory signaling. Positive regulation of 11β-HSD1 by C/EBPβ may link amplification of glucocorticoid action with metabolic and inflammatory pathways and may represent an endogenous innate host-defense mechanism.

scholarly journals CCAAT-enhancer-binding protein-beta expression in vivo is associated with muscle strength

Aging Cell ◽  
2012 ◽  
Vol 11 (2) ◽  
pp. 262-268 ◽  
Author(s):  
Lorna W. Harries ◽  
Luke C. Pilling ◽  
L. Dena G. Hernandez ◽  
Rachel Bradley-Smith ◽  
William Henley ◽  
...  
Keyword(s):  
Muscle Strength ◽  
Binding Protein ◽  
Enhancer Binding Protein ◽  
Ccaat Enhancer Binding Protein

CDDO Increases Translation of CCAAT Enhancer Binding Protein alpha To Induce Granulocytic Differentiation.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 2458-2458 ◽  
Author(s):  
Steffen Koschmieder ◽  
Francesco D′Alo′ ◽  
Hanna Radomska ◽  
Susumu Kobayashi ◽  
Elena Levantini ◽  
...  
Keyword(s):  
De Novo ◽  
Binding Protein ◽  
Northern Blotting ◽  
Granulocytic Differentiation ◽  
Protein Levels ◽  
Enhancer Binding Protein ◽  
Ccaat Enhancer Binding Protein ◽  
Eif2 Alpha

Abstract The triterpenoid 2-Cyano-3,12-dioxooleana-1,9-dien-28-oic acid (CDDO) is a novel antineoplastic drug which induces apoptosis of a wide variety of tumor cells in vitro and in vivo and leads to granulocytic differentiation of hematopoietic progenitor cells. We studied the effect of CDDO on CCAAT enhancer binding protein alpha (CEBPA), a transcription factor which is critical for granulocytic differentiation. In HL60 myeloblastic cells, CDDO (0.01 to 2 uM) dose-dependently decreased the number of cells in culture and increased the fraction of apoptotic cells. However, at doses which did not induce apoptosis, CDDO increased the number of granulocytic cells, as assessed by morphology, NBT assay, and FACS, and Northern blotting showed an increase of GCSFR and a decrease of c-myc mRNA. Phagocytosis of FITC-labeled E. coli bacteria by these cells was enhanced by CDDO. While CEBPA mRNA was decreased, CEBPA protein was significantly increased within 24 hours of treatment, and this was not abrogated by preincubation with the caspase inhibitor Z-DEVD-fmk, again suggesting that these effects were independent of apoptosis. CDDO increased the ratio of the transcriptionally active isoform p42 and the inactive p30 isoform 3-fold, and gel shift assays showed enhanced DNA binding to a GCSFR promoter probe. Since eukaryotic translation initiation factors (eIF) have been described to alter the CEBPA protein isoform ratio, we studied the effects of CDDO on eiF2 alpha and eiF4E activity. CDDO increased the phosphorylation of eIF4E and decreased the phosphorylation of eIF2 alpha within 5 hours of treatment, and this was associated with an increase of the p42/p30 CEBPA ratio. In the presence of the translation inhibitor cycloheximide, CEBPA protein levels decreased after 2 hours, suggesting that CDDO did not stabilize CEBPA and that de novo protein synthesis was required for the observed effects. The effect of CDDO on the p42/p30 ratio was mimicked by 2-AP, which inhibits eIF2 alpha phosphorylation, but was independent of PPARgamma and TGFß pathways, as demonstrated by preincubation with GW9662, or TGFß1, respectively. In primary blasts from patients with acute myeloid leukemia (AML), the p42/p30 ratio of CEBPA was enhanced by CDDO treatment. In conclusion, CDDO leads to granulocytic differentiation and translational induction of CEBPA protein. Since CEBPA function is impaired in many patients with AML, CDDO may provide a novel treatment approach for these patients.

scholarly journals Impairment of Natural Killer Cytotoxic Activity and Interferon γ Production in Ccaat/Enhancer Binding Protein γ–Deficient Mice

1999 ◽  
Vol 190 (11) ◽  
pp. 1573-1582 ◽  
Author(s):  
Tsuneyasu Kaisho ◽  
Hiroko Tsutsui ◽  
Takashi Tanaka ◽  
Tohru Tsujimura ◽  
Kiyoshi Takeda ◽  
...  
Keyword(s):  
Cytotoxic Activity ◽  
Nk Cells ◽  
Natural Killer ◽  
Binding Protein ◽  
Normal Surface ◽  
Enhancer Binding Protein ◽  
Ccaat Enhancer Binding Protein ◽  
Ifn Γ

We have investigated in vivo roles of CCAAT/enhancer binding protein γ (C/EBPγ) by gene targeting. C/EBPγ-deficient (C/EBPγ2/−) mice showed a high mortality rate within 48 h after birth. To analyze the roles of C/EBPγ in lymphoid lineage cells, bone marrow chimeras were established. C/EBPγ2/− chimeras showed normal T and B cell development. However, cytolytic functions of their splenic natural killer (NK) cells after stimulation with cytokines such as interleukin (IL)-12, IL-18, and IL-2 were significantly reduced as compared with those of control chimera NK cells. In addition, the ability of C/EBPγ−/− chimera splenocytes to produce interferon (IFN)-γ in response to IL-12 and/or IL-18 was markedly impaired. NK cells could be generated in vitro with normal surface marker expression in the presence of IL-15 from C/EBPγ2/− newborn spleen cells. However, they also showed lower cytotoxic activity and IFN-γ production when stimulated with IL-12 plus IL-18 than control NK cells, as observed in C/EBPγ2/− chimera splenocytes. In conclusion, our study reveals that C/EBPγ is a critical transcription factor involved in the functional maturation of NK cells.

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