Induction of angiotensin I-converting enzyme transcription by a protein kinase C-dependent mechanism in human endothelial cells.
Angiotensin I-converting enzyme (ACE) has been implicated in various cardiovascular diseases; however, little is known about the ACE gene regulation in endothelial cells. We have investigated the effect of the protein kinase C activator phorbol 12-myristate 13-acetate (PMA) on ACE activity and gene expression in human umbilical vein endothelial cells (HUVEC). Our results showed a 3- and 5-fold increase in ACE activity in the medium and in the cells, respectively, after 24-h stimulation by PMA. We also observed an increase in the cellular ACE mRNA content starting after 6 h and reaching a 10-fold increase at 24 h in response to 100 ng/ml PMA as measured by ribonuclease protection assay. This effect was mediated by an increased transcription of the ACE gene as demonstrated by nuclear run-on experiments and nearly abolished by the specific PKC inhibitor GF 109203X. Our results indicate that PMA-activated PKC strongly increases ACE mRNA level and ACE gene transcription in HUVEC, an effect associated with an increased ACE secretion. A role for early growth response factor-1 (Egr-1) as a factor regulating ACE gene expression is suggested by both the presence of an Egr-1-responsive element in the proximal portion of the ACE promoter and the kinetics of the Egr-1 mRNA increase in HUVEC treated with PMA.
Villard
E
E
INSERM Unité 358, Hôpital Saint-Louis, 1 avenue Claude Vellefaux, 75475 Paris Cedex 10, France.
Alonso
A
A
Agrapart
M
M
Challah
M
M
Soubrier
F
F
D001483:Base Sequence; D002478:Cells, Cultured; D017931:DNA Primers; D004730:Endothelium, Vascular / Q000166:cytology / Q000201:enzymology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015971:Gene Expression Regulation, Enzymologic; D006801:Humans; D007703:Peptidyl-Dipeptidase A / Q000235:genetics*; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014158:Transcription, Genetic
D017931:DNA Primers; D004791:Enzyme Inhibitors; D012333:RNA, Messenger; D011493:Protein Kinase C; D007703:Peptidyl-Dipeptidase A; D013755:Tetradecanoylphorbol Acetate