title: Nitrooleate mediates nitric oxide synthase activation in endothelial cells.
abstract: Nitrated lipids such as nitrooleate (OLA-NO2) can act as endogenous peroxisome proliferator-activated receptor gamma (PPARγ) ligands to exert vascular protective effects. However, the molecular mechanisms regarding nitric oxide (NO) production and its regulation are not fully defined in the vasculature. Here, we show that OLA-NO2 increased endothelial NO release by modulating activation of endothelial nitric oxide synthase (eNOS) in endothelial cells. Treatment with OLA-NO2 (3 μM) increased NO release in a time-dependent manner. OLA-NO2 decreased protein expression of eNOS and caveolin-1 (Cav-1) but increased heat shock protein 90 (Hsp90) expression. Immunoprecipitation analysis confirmed that OLA-NO2 replaced eNOS/Cav-1 with eNOS/Hsp90 interaction, resulting in increasing eNOS activity. OLA-NO2 also induced eNOS phosphorylation at Ser633 and Ser1177 and eNOS dephosphorylation at Ser113 and Thr495. In addition, OLA-NO2 induced phosphorylation of Akt and extracellular signal-regulated protein kinase (ERK1/2), which might contribute to eNOS activation. Collectively, these results substantiate a new functional role for nitrated fatty acid, demonstrating that OLA-NO2 exerts vascular protective effects by increasing NO bioavailability through eNOS phosphorylation/dephosphorylation and interaction with associated proteins such as Hsp90 and Cav-1.
authors.affiliation: Department of Food and Nutrition, College of Natural Sciences, Myongji University, YongIn, 449-728, Korea.
authors.forename: Eunju
authors.initials: E
authors.lastname: Shin
authors.forename: Eunju
authors.initials: E
authors.lastname: Yeo
authors.forename: Jihye
authors.initials: J
authors.lastname: Lim
authors.forename: Yun Hee
authors.initials: YH
authors.lastname: Chang
authors.forename: Haeryun
authors.initials: H
authors.lastname: Park
authors.forename: Eugene
authors.initials: E
authors.lastname: Shim
authors.forename: Haeyon
authors.initials: H
authors.lastname: Chung
authors.forename: Hye Jin
authors.initials: HJ
authors.lastname: Hwang
authors.forename: Jiyeon
authors.initials: J
authors.lastname: Chun
authors.forename: Jinah
authors.initials: J
authors.lastname: Hwang
mesh_terms: D002478:Cells, Cultured; D004789:Enzyme Activation / Q000187:drug effects; D061307:Human Umbilical Vein Endothelial Cells / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D009569:Nitric Oxide / Q000096:biosynthesis; D019001:Nitric Oxide Synthase / Q000235:genetics / Q000378:metabolism*; D009574:Nitro Compounds / Q000737:chemistry / Q000494:pharmacology*; D009829:Oleic Acids / Q000737:chemistry / Q000494:pharmacology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013329:Structure-Activity Relationship
chemical_list: D009574:Nitro Compounds; D009829:Oleic Acids; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase