COUP-TFII is regulated by high glucose in endothelial cells.
Diabetes mellitus is an important risk factor for cardiovascular diseases. Clinical evidence supports a link between hyperglycemia, endothelial dysfunction, and vascular disorders. However, the precise molecular mechanisms causing endothelial dysfunction in diabetic patients remain unclear. An interesting novel mediator could be chicken ovalbumin upstream promoter-transcription factor II (COUP-TFII), which plays an essential role in glucose metabolism. COUP-TFII is known to be expressed in venous endothelial cells. In this study, we show COUP-TFII expression in human umbilical vein endothelial cells (HUVECs) and human coronary artery endothelial cells. HUVECs express glucose transporters 1, 3, 6, and 10, and the insulin receptor. Insulin in combination with glucose activates protein kinase B (PKB or Akt) phosphorylation via phosphoinositide 3-kinase (PI3-kinase). Short-term (60-240 min) stimulation of HUVECs with high glucose increased COUP-TFII expression independent of insulin. Long-term (48 h) stimulation of HUVECs with high glucose augmented expression of the insulin receptor and E-selectin, but downregulated COUP-TFII protein expression. Downregulation of COUP-TFII by shRNA leads to downregulation of E-selectin and upregulation of eNOS and glucose transporters. Our data suggest that COUP-TFII is regulated by glucose in a time- and dose-dependent manner in endothelial cells. COUP-TFII might affect endothelial function in a diabetic background.
Department of Medicine III, University Hospital Carl Gustav Carus, Dresden University of Technology, Germany.
C
C
Brunssen
S
S
Korten
M
M
Brux
S
S
Seifert
J
J
Roesler
S R
SR
Bornstein
H
H
Morawietz
W
W
Goettsch
D015153:Blotting, Western; D051837:COUP Transcription Factor II / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D002478:Cells, Cultured; D003331:Coronary Vessels / Q000166:cytology; D004305:Dose-Response Relationship, Drug; D019040:E-Selectin / Q000235:genetics / Q000378:metabolism; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects*; D005947:Glucose / Q000494:pharmacology*; D006801:Humans; D007328:Insulin / Q000378:metabolism; D052250:Nitric Oxide Synthase Type III / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011972:Receptor, Insulin / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors; D014471:Umbilical Veins / Q000166:cytology
D051837:COUP Transcription Factor II; D019040:E-Selectin; D007328:Insulin; D012333:RNA, Messenger; C496314:NOS3 protein, human; D052250:Nitric Oxide Synthase Type III; D011972:Receptor, Insulin; D005947:Glucose