Preview |
PDF (Original Article)
- Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
1MB |
Item Type: | Article |
---|---|
Title: | 11,12-Epoxyeicosatrienoic acid-induced inhibition of FOXO factors promotes endothelial proliferation by down-regulating p27(Kip1) |
Creators Name: | Potente, M., Fisslthaler, B., Busse, R. and Fleming, I. |
Abstract: | Cytochrome P450-derived epoxyeicosatrienoic acids (EETs) stimulate endothelial cell proliferation and angiogenesis. In this study, we investigated the involvement of the forkhead box, class O (FOXO) family of transcription factors and their downstream target p27(Kip1) in EET-induced endothelial cell proliferation. Incubation of human umbilical vein endothelial cells with 11,12-EET induced a time- and dose-dependent decrease in p27(Kip1) protein expression, whereas p21(Cip1) was not significantly affected. This effect on p27(Kip1) protein was associated with decreased mRNA levels as well as p27(Kip1) promoter activity. 11,12-EET also stimulated the time-dependent phosphorylation of Akt and of the forkhead factors FOXO1 and FOXO3a, effects prevented by the phosphatidylinositol 3-kinase inhibitor LY 294002. Transfection of endothelial cells with either a dominant-negative or an "Akt-resistant"/constitutively active FOXO3a mutant reversed the 11,12-EET-induced down-regulation of p27(Kip1), whereas transfection of a constitutive active Akt decreased p27(Kip1) expression independently of the presence or absence of 11,12-EET. To determine whether these effects are involved in EET-induced proliferation, endothelial cells were transfected with the 11,12-EET-generating epoxygenase CYP2C9. Transfection of CYP2C9 elicited endothelial cell proliferation and this effect was inhibited in cells co-transfected with CYP2C9 and either a dominant-negative Akt or constitutively active FOXO3a. Reducing FOXO expression using RNA interference, on the other hand, attenuated p27(Kip1) expression and stimulated endothelial cell proliferation. These results indicate that EET-induced endothelial cell proliferation is associated with the phosphatidylinositol 3-kinase/Akt-dependent phosphorylation and inactivation of FOXO factors and the subsequent decrease in expression of the cyclin-dependent kinase inhibitor p27(Kip1). |
Keywords: | 8,11,14-Eicosatrienoic Acid, Aryl Hydrocarbon Hydroxylases, Cell Cycle Proteins, Cell Division, Cultured Cells, Cyclin-Dependent Kinase Inhibitor p27, Cytochrome P-450 CYP2C9, DNA-Binding Proteins, Dominant Genes, Down-Regulation, Drug Dose-Response Relationship, Enzyme Inhibitors, Forkhead Box Protein O1, Forkhead Transcription Factors, Genetic Promoter Regions, Immunoblotting, Luciferases, Messenger RNA, Northern Blotting, Phosphoinositide-3 Kinase Inhibitors, Phosphorylation, Physiologic Neovascularization, Plasmids, Small Interfering RNA, Time Factors, Transcription Factors, Transfection, Tumor Suppressor Proteins, Umbilical Veins, Vascular Endothelium, Vasodilator Agents, Western Blotting |
Source: | Journal of Biological Chemistry |
ISSN: | 0021-9258 |
Publisher: | American Society for Biochemistry and Molecular Biology |
Volume: | 278 |
Number: | 32 |
Page Range: | 29619-29625 |
Date: | 4 January 2021 |
Additional Information: | Copyright © 2003 ASBMB. Currently published by Elsevier Inc; originally published by American Society for Biochemistry and Molecular Biology. This is an Open Access article under the CC BY license. |
Official Publication: | https://doi.org/10.1074/jbc.M305385200 |
PubMed: | View item in PubMed |
Repository Staff Only: item control page