title: Ferulic acid enhances nitric oxide production through up-regulation of argininosuccinate synthase in inflammatory human endothelial cells.
abstract: OBJECTIVE
  In this study, we investigated the protective effect of ferulic acid (FA) on nitric oxide (NO) production in tumor necrosis factor (TNF)-α-stimulated inflammatory human umbilical vein endothelial cells (HUVECs), and elucidated the mechanism(s) involved.
  
  
  METHODS
  The TNF-α-stimulated inflammatory HUVECs were treated with acetylcholine (ACh) and/or FA. NO productions were measured by monitoring nitrite and nitrate using a 2,3-diaminonaphthalene Kit. Expressions of mRNA and proteins were evaluated by RT-PCR and Western blotting, respectively.
  
  
  RESULTS
  FA treatment resulted in a dose-dependent (10-200μM) restoration of ACh-mediated NO production in TNF-α-treated HUVECs, whereas treatment with the FA analogues, coumaric acid, and apocynin resulted in no significant effect. FA treatment had no effect on O2(-) production in TNF-α-stimulated HUVECs. N(G)-monomethyl-l-arginine acetate (a nitric oxide synthase (NOS) inhibitor) and α-methyl-dl-aspartic acid (an argininosuccinate synthase (ASS) inhibitor) counteracted the effects of FA on the NO production. While FA treatment did not significantly affect the protein expression of p-eNOS or eNOS, the protein expression of ASS as well as mRNA expression was restored to normal levels upon exposure to FA in TNF-α-stimulated HUVECs. In nucleus, FA attenuated the increase of nuclear factor-kappa B (NF-κB) expression by TNF-α.
  
  
  CONCLUSIONS
  FA treatment rescues the defect in ACh-induced NO production resulting from TNF-α-stimulation in inflammatory HUVECs. This effect was likely due, in part, to the FA-mediated up-regulation of ASS expression via the suppression of NF-κB inflammatory signaling cascade.
authors.affiliation: Faculty of Agriculture, Graduate School of Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
authors.forename: Jian
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Faculty of Agriculture, Graduate School of Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
authors.forename: Aki
authors.initials: A
authors.lastname: Suyama
authors.affiliation: Faculty of Agriculture, Graduate School of Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
authors.forename: Hsuan
authors.initials: H
authors.lastname: Chung
authors.affiliation: Faculty of Agriculture, Graduate School of Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Fukuda
authors.affiliation: Faculty of Agriculture, Graduate School of Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan. Electronic address: mitsurut@agr.kyushu-u.ac.jp.
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Tanaka
authors.affiliation: Faculty of Agriculture, Graduate School of Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
authors.forename: Toshiro
authors.initials: T
authors.lastname: Matsui
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D001124:Argininosuccinate Synthase / Q000235:genetics / Q000276:immunology*; D003373:Coumaric Acids / Q000494:pharmacology*; D061307:Human Umbilical Vein Endothelial Cells / Q000187:drug effects* / Q000276:immunology; D006801:Humans; D016328:NF-kappa B / Q000276:immunology; D009569:Nitric Oxide / Q000276:immunology*; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology*; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D003373:Coumaric Acids; D016328:NF-kappa B; D014409:Tumor Necrosis Factor-alpha; D009569:Nitric Oxide; C004999:ferulic acid; D001124:Argininosuccinate Synthase
keywords: Argininosuccinate synthase; Ferulic acid; Inflammation; Nitric oxide; Tumor necrosis factor-α