title: N-terminal domain of soluble epoxide hydrolase negatively regulates the VEGF-mediated activation of endothelial nitric oxide synthase.
abstract: OBJECTIVE
  The mammalian soluble epoxide hydrolase (sEH) has both an epoxide hydrolase and a phosphatase domain. The role of sEH hydrolase activity in the metabolism of epoxyeicosatrienoic acids (EETs) and the activation of endothelial nitric oxide synthase (eNOS) in endothelial cells (ECs) has been well defined. However, far less is known about the role of sEH phosphatase activity in eNOS activation. In the present study, we investigated whether the phosphatase domain of sEH was involved in the eNOS activation in ECs.
  
  
  RESULTS
  The level of eNOS phosphorylation in aortas is higher in the sEH knockout (sEH(-/-)) mice than in wild-type mice. In ECs, pharmacological inhibition of sEH phosphatase or overexpressing sEH with an inactive phosphatase domain enhanced vascular endothelial growth factor (VEGF)-induced NO production and eNOS phosphorylation. In contrast, overexpressing the phosphatase domain of sEH prevented the VEGF-mediated NO production and eNOS phosphorylation at Ser617, Ser635, and Ser1179. Additionally, treatment with VEGF induced a c-Src kinase-dependent increase in transient tyrosine phosphorylation of sEH and the formation of a sEH-eNOS complex, which was abolished by treatment with a c-Src kinase inhibitor, PP1, or the c-Src dominant-negative mutant K298M. We also demonstrated that the phosphatase domain of sEH played a key role in VEGF-induced angiogenesis by detecting the tube formation in ECs and neovascularization in Matrigel plugs in mice.
  
  
  CONCLUSIONS
  In addition to epoxide hydrolase activity, phosphatase activity of sEH plays a pivotal role in the regulation of eNOS activity and NO-mediated EC functions.
authors.affiliation: Institute of Physiology, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Hsin-Han
authors.initials: HH
authors.lastname: Hou
authors.forename: Bruce D
authors.initials: BD
authors.lastname: Hammock
authors.forename: Kou-Hui
authors.initials: KH
authors.lastname: Su
authors.forename: Christophe
authors.initials: C
authors.lastname: Morisseau
authors.forename: Yu Ru
authors.initials: YR
authors.lastname: Kou
authors.forename: Susumu
authors.initials: S
authors.lastname: Imaoka
authors.forename: Ami
authors.initials: A
authors.lastname: Oguro
authors.forename: Song-Kun
authors.initials: SK
authors.lastname: Shyue
authors.forename: Jin-Feng
authors.initials: JF
authors.lastname: Zhao
authors.forename: Tzong-Shyuan
authors.initials: TS
authors.lastname: Lee
mesh_terms: D000818:Animals; D001011:Aorta / Q000378:metabolism; D001483:Base Sequence; D000081247:CSK Tyrosine-Protein Kinase; D017931:DNA Primers / Q000235:genetics; D004789:Enzyme Activation; D004851:Epoxide Hydrolases / Q000737:chemistry* / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D018919:Neovascularization, Physiologic; D052250:Nitric Oxide Synthase Type III / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000235:genetics; D012995:Solubility; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism*; D019061:src-Family Kinases
chemical_list: D017931:DNA Primers; D042461:Vascular Endothelial Growth Factor A; C467480:vascular endothelial growth factor A, mouse; D052250:Nitric Oxide Synthase Type III; C496315:Nos3 protein, mouse; D011505:Protein-Tyrosine Kinases; D000081247:CSK Tyrosine-Protein Kinase; D019061:src-Family Kinases; D004851:Epoxide Hydrolases; C518648:Ephx2 protein, mouse
references.citation: Annu Rev Biochem. 1994;63:175-95
references.pmid: 7526779
references.citation: J Biol Chem. 1997 Jul 25;272(30):18522-5
references.pmid: 9228013
references.citation: Prostaglandins Other Lipid Mediat. 2007 Jan;82(1-4):162-74
references.pmid: 17164144
references.citation: Arterioscler Thromb Vasc Biol. 2009 Jan;29(1):54-60
references.pmid: 18927469
references.citation: Cardiovasc Res. 2009 Jun 1;82(3):468-75
references.pmid: 19307231
references.citation: Biol Pharm Bull. 2009 Dec;32(12):1962-7
references.pmid: 19952412
references.citation: Proc Natl Acad Sci U S A. 2003 Feb 18;100(4):1552-7
references.pmid: 12574508
references.citation: J Cardiovasc Pharmacol. 2008 Oct;52(4):314-23
references.pmid: 18791465
references.citation: Circ Res. 2000 Nov 24;87(11):992-8
references.pmid: 11090543
references.citation: Proc Natl Acad Sci U S A. 2008 Dec 2;105(48):18901-6
references.pmid: 19028872
references.citation: Antioxid Redox Signal. 2008 Jun;10(6):1115-26
references.pmid: 18321209
references.citation: Prog Lipid Res. 2004 Jan;43(1):55-90
references.pmid: 14636671
references.citation: J Biol Chem. 1992 Oct 25;267(30):21277-80
references.pmid: 1383221
references.citation: J Clin Invest. 2009 Jul;119(7):2009-18
references.pmid: 19487814
references.citation: Cardiovasc Drug Rev. 2006 Summer;24(2):169-88
references.pmid: 16961727
references.citation: Am J Physiol Lung Cell Mol Physiol. 2005 Nov;289(5):L739-49
references.pmid: 15964899
references.citation: J Biol Chem. 2001 May 25;276(21):17625-8
references.pmid: 11292821
references.citation: Trends Mol Med. 2004 Apr;10(4):143-5
references.pmid: 15162796
references.citation: Circ Res. 2004 Sep 3;95(5):471-8
references.pmid: 15271857
references.citation: Cardiovasc Res. 2007 Jul 15;75(2):247-60
references.pmid: 17466957
references.citation: Crit Care Med. 2008 Sep;36(9):2597-606
references.pmid: 18679109
references.citation: Proc Natl Acad Sci U S A. 2009 Jan 13;106(2):564-9
references.pmid: 19126686
references.citation: Proc Natl Acad Sci U S A. 2003 Feb 18;100(4):1558-63
references.pmid: 12574510
references.citation: J Biol Chem. 2008 Oct 24;283(43):29069-76
references.pmid: 18682401
references.citation: J Mol Biol. 1999 Dec 17;294(5):1351-62
references.pmid: 10600390
references.citation: Circ Res. 2002 Dec 13;91(12):1160-7
references.pmid: 12480817
references.citation: J Histochem Cytochem. 2004 Apr;52(4):447-54
references.pmid: 15033996
references.citation: J Biol Chem. 2000 Dec 22;275(51):40504-10
references.pmid: 11001943
references.citation: Cardiovasc Res. 2010 Jan 1;85(1):232-40
references.pmid: 19679679
references.citation: Circulation. 2006 Dec 12;114(24):2655-62
references.pmid: 17116771
references.citation: Circ Res. 2009 Jan 2;104(1):50-9
references.pmid: 19038867
references.citation: Hypertension. 2002 Feb;39(2 Pt 2):690-4
references.pmid: 11882632
references.citation: Annu Rev Physiol. 1995;57:707-36
references.pmid: 7539994
references.citation: Biochem Pharmacol. 2002 May 1;63(9):1599-608
references.pmid: 12007563
references.citation: Mol Biol Cell. 2007 Nov;18(11):4659-68
references.pmid: 17855507
references.citation: Arterioscler Thromb Vasc Biol. 2003 Feb 1;23(2):211-7
references.pmid: 12588761
references.citation: Proc Natl Acad Sci U S A. 2008 Jun 3;105(22):7738-43
references.pmid: 18509061
references.citation: Biochem Pharmacol. 1980 Feb;29(3):389-95
references.pmid: 7362652
references.citation: Biochem Biophys Res Commun. 2006 Mar 3;341(1):254-60
references.pmid: 16414022