Faculty Collaboration Database

Mechanisms of activation of eNOS by 20-HETE and VEGF in bovine pulmonary artery endothelial cells. Am J Physiol Lung Cell Mol Physiol 2006 Sep;291(3):L378-85

Date

05/09/2006

Pubmed ID

16679377

DOI

10.1152/ajplung.00424.2005

Scopus ID

2-s2.0-33748439111 (requires institutional sign-in at Scopus site)   49 Citations

Abstract

We have demonstrated that VEGF-induced dilation of bovine pulmonary arteries is associated with activation of cytochrome P-450 family 4 (CYP4) enzymes and eNOS. We hypothesized that VEGF and the CYP4 product 20-HETE would trigger common downstream pathways of intracellular signaling to activate eNOS. We treated bovine pulmonary artery endothelial cells (BPAECs) with 20-HETE (1 microM) or VEGF (8.3 nM) and examined three molecular events known to activate eNOS: 1) phosphorylation at serine 1179, 2) phosphorylation of protein kinase B (Akt), which subsequently phosphorylates eNOS, and 3) association of eNOS with 90-kDa heat shock protein (Hsp90). Both 20-HETE and VEGF increase the phosphorylation of eNOS at serine 1179 and Akt at serine 473. The CYP4 inhibitor dibromododecynyl methyl sulfonamide (DDMS) blocks VEGF-induced phosphorylation of eNOS. VEGF had no effect on the binding of Hsp90 with eNOS, whereas 20-HETE decreased the association of the protein partners. Inhibition of Akt-phosphatidylinositol 3-kinase with wortmannin blocks both 20-HETE and VEGF-induced relaxation of pulmonary arteries, supporting the functional contribution of Akt phosphorylation to the vasoactive actions of both agents. Treatment with radicicol had no effect on 20-HETE-induced relaxation of pulmonary arteries, consistent with an absence of effect on association of Hsp90 to eNOS, whereas radicicol partially blocked VEGF-evoked relaxations, possibly secondary to effects on endpoints other than Hsp90 association with eNOS. In conclusion, VEGF and 20-HETE share eNOS activation pathways, including phosphorylation of serine 1179 and phosphorylation of Akt. Unlike aortic endothelial cells, eNOS activation in BPAECs by either VEGF or 20-HETE does not appear to require increased association of Hsp90.

Author List

Chen Y, Medhora M, Falck JR, Pritchard KA Jr, Jacobs ER

Author

Kirkwood A. Pritchard PhD Professor in the Surgery department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
Cattle
Cells, Cultured
Drug Synergism
Endothelium, Vascular
Enzyme Activation
HSP90 Heat-Shock Proteins
Hydroxyeicosatetraenoic Acids
In Vitro Techniques
Nitric Oxide Synthase Type III
Phosphorylation
Proto-Oncogene Proteins c-akt
Pulmonary Artery
Serine
Vascular Endothelial Growth Factor A