Crucial roles of GATA-2 and SP1 in adrenomedullin-affected expression of tissue factor pathway inhibitor in human umbilical vein endothelial cells exposed to lipopolysaccharide.
Thromb Haemost
; 97(5): 839-46, 2007 May.
Article
in En
| MEDLINE
| ID: mdl-17479196
ABSTRACT
Adrenomedullin (ADM) is a vasodilator peptide that has a variety of effects, including antithrombotic activities and resistant roles to lipopolysaccharide (LPS)-induced septic shock. During sepsis, LPS triggers the development of disseminated intravascular coagulation (DIC) via the tissue factor-dependent pathway of coagulation. It is unknown whether the antithrombotic activities of ADM contribute to its resistance to sepsis. In the present study, we investigated the effects of ADM on tissue factor pathway inhibitor (TFPI) (primary anticoagulant factor) expression in human umbilical vein endothelial cells (HUVECs) exposed to LPS, and the possible underlying mechanism for these effects. Exposure of HUVECs to LPS for 12 hours caused significant decrease of TFPI protein activities and mRNA expression. These effects were abolished by treatment with ADM (10(-10) to 10(-6) M), cAMP analogue and calcium antagonist. Accordingly, cAMP antagonist inhibited the counteraction effect of ADM on LPS in TFPI expression. Electrophoresis mobility shift assay (EMSA) and Western blot analysis showed that the protein level of GATA-2 and SP1 transcriptional factors and their binding to the corresponding regulatory sequences decreased by LPS treatment. And these effects of LPS were antagonized by ADM. Promoter-reporter assays and mutational analysis also confirmed the roles of GATA-2 and SP1 motifs from -1247 to -381 bp promoter sequence in TFPI inducible expression. Taken together, these results indicate that ADM antagonizes the effect of LPS on TFPI expression, which is mediated by affecting transcriptional factor GATA-2 and SP1 through cAMP and calcium signaling pathway.
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Collection:
01-internacional
Database:
MEDLINE
Main subject:
Lipopolysaccharides
/
Sp1 Transcription Factor
/
Endothelial Cells
/
GATA2 Transcription Factor
/
Adrenomedullin
/
Lipoproteins
Limits:
Humans
Language:
En
Journal:
Thromb Haemost
Year:
2007
Type:
Article
Affiliation country:
China