Tumor necrosis factor-alpha upregulates angiopoietin-2 in human umbilical vein endothelial cells.
The angiopoietin-Tie2 system is an important regulator of vasculogenesis and vascular integrity. Angiopoietin-2 (Ang2) disrupts blood vessel formation in the developing embryo by antagonizing the effects of angiopoietin-1 (Ang1) on the Tie2 receptor. In this study, we examined the effect of a well-known proinflammatory cytokine, tumor necrosis factor-alpha (TNF-alpha), on Ang2 expression in human umbilical vein endothelial cells. Reverse transcriptase-polymerase chain reaction and Northern blot analyses indicated that TNF-alpha induced Ang2 mRNA expression in a time- and dose-dependent manner. Western blot analyses revealed that TNF-alpha treatment increased cellular Ang2 protein. TNF-alpha induced less Ang2 mRNA expression in the presence of nuclear factor-kappaB (NF-kappaB) inhibitor. These results suggest that TNF-alpha-induced inflammatory angiogenesis might be facilitated by the induction of Ang2.
Kim
I
I
National Creative Research Initiatives Center for Cardiac Regeneration and Institute of Cardiovascular Research, Chonbuk University School of Medicine, Chonju, Korea.
Kim
J H
JH
Ryu
Y S
YS
Liu
M
M
Koh
G Y
GY
D042702:Angiopoietin-2; D001483:Base Sequence; D017931:DNA Primers; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D016328:NF-kappa B / Q000037:antagonists & inhibitors; D009389:Neovascularization, Pathologic / Q000235:genetics; D011506:Proteins / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics; D011994:Recombinant Proteins / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D014471:Umbilical Veins / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D015854:Up-Regulation / Q000187:drug effects*
D042702:Angiopoietin-2; D017931:DNA Primers; D016328:NF-kappa B; D011506:Proteins; D012333:RNA, Messenger; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha