Tumor necrosis factor alpha and phorbol 12-myristate-13-acetate down-regulate human 11beta-hydroxysteroid dehydrogenase type 2 through p50/p50 NF-kappaB homodimers and Egr-1.
The 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2) regulates access of 11beta-hydroxyglucocorticoids to the mineralocorticoid receptor by reducing the hydroxyl group of these steroids at position 11. Previous cell culture studies revealed that tumor necrosis factor-alpha (TNF-alpha) down-regulates 11beta-HSD2 activity. Here, we demonstrate that transgenic mice overexpressing TNF-alpha have decreased mRNA abundance and activity of 11beta-HSD2 in kidney tissue, indicating that this effect may occur also in vivo. The analysis of the transcriptional regulation of 11beta-HSD2 by TNF-alpha and phorbol 12-myristate-13-acetate (PMA) with in vivo genomic footprinting in human colon SW620 cells revealed stimulus-dependent protein-DNA interactions in three promoter regions, kappaB1, Sp1/Egr-1I, and Sp1/Egr-1II. Chromatin immunoprecipitation and electrophoretic mobility shift assays demonstrated the relevance of NF-kappaB binding to kappaB1 and of Egr-1 binding to Sp1/Egr-1 sites for the PMA and TNF-alpha effect. We observed a temporal switch of binding to kappaB1 site from active p65/p50 heterodimers to inactive p50/p50 homodimers. TNF-alpha or PMA treatment for 24 h resulted in accumulation of p50 and decrease of p65 nuclear proteins. Overexpression of p50 inhibited HSD11B2 promoter activity and overexpression of Egr-1 inhibited transactivation of the HSD11B2 promoter by p65/p50. In conclusion, TNF-alpha and PMA down-regulate expression and activity of 11beta-HSD2 most likely by a coordinate binding of p50/p50 and Egr-1 to the HSD11B2 promoter.
Kostadinova
Radina M
RM
Department of Nephrology and Hypertension, University Hospital, Bern, Switzerland.
Nawrocki
Andrea R
AR
Frey
Felix J
FJ
Frey
Brigitte M
BM
D043209:11-beta-Hydroxysteroid Dehydrogenase Type 2 / Q000235:genetics* / Q000378:metabolism; D000818:Animals; D002460:Cell Line; D003106:Colon; D004247:DNA / Q000378:metabolism; D018983:DNA Footprinting; D019281:Dimerization; D051766:Early Growth Response Protein 1 / Q000378:metabolism / Q000502:physiology*; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects*; D006801:Humans; D007668:Kidney / Q000201:enzymology; D051379:Mice; D008822:Mice, Transgenic; D052002:NF-kappa B p50 Subunit / Q000378:metabolism / Q000502:physiology*; D011401:Promoter Regions, Genetic / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000494:pharmacology* / Q000502:physiology
D051766:Early Growth Response Protein 1; C486109:Egr1 protein, mouse; D052002:NF-kappa B p50 Subunit; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D004247:DNA; D043209:11-beta-Hydroxysteroid Dehydrogenase Type 2; D013755:Tetradecanoylphorbol Acetate