Abstract
OBJECTIVE - We evaluated the full range effects of FOXO3a in endothelial cells (ECs) by microarray analysis and investigated the role of FOXO3a regulating TNF receptor signaling pathway. METHODS AND RESULTS - Human umbilical vein endothelial cells (HUVECs) were transfected with adenoviral vectors expressing constitutively active FOXO3a (Ad-TM-FOXO3a). Ad-TM-FOXO3a transfection caused remarkable apoptosis, which were accompanied with upregulation of genes related with TNF receptor signaling, such as TNF-α, TANK (TRAF-associated NF-κB activator), and TTRAP (TRAF and TNF receptor-associated protein). Furthermore, κB-Ras1 (IκB-interacting Ras-like protein-1) which is known to block IκB degradation was found increased, and intranuclear translocation of NF-κB was inhibited. GADD45β and XIAP, negative regulators of c-Jun N-terminal kinase (JNK), were suppressed and JNK activity was increased. Attenuation of TNF signaling pathway either by blocking antibody for TNF receptor or by blocking JNK with DMAP (6-dimethylaminopurine) or Ad-TAM67 (dominant negative c-Jun) cotransfection, significantly reduced FOXO3a-induced apoptosis. Finally, treatment of vasculature with heat shock, an activator of endogenous FOXO3a, resulted in EC apoptosis, which was completely rescued by Ad-TAM67. CONCLUSION - FOXO3a promotes apoptosis of ECs, through activation of JNK and suppression of NF-κB. These data identify a novel role of FOXO3a to turn TNF receptor signaling to a proapoptotic JNK-dependent pathway.
Original language | English (US) |
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Pages (from-to) | 112-120 |
Number of pages | 9 |
Journal | Arteriosclerosis, thrombosis, and vascular biology |
Volume | 28 |
Issue number | 1 |
DOIs | |
State | Published - Jan 2008 |
Externally published | Yes |
Keywords
- Apoptosis
- FOXO3a
- JNK
- NF-κB
ASJC Scopus subject areas
- Cardiology and Cardiovascular Medicine