title: 3-Nitrotyrosine inhibits fibroblast-mediated collagen gel contraction and chemotaxis.
abstract: Reactive nitrogen species induce tissue inflammation and nitrate tyrosine residues of various kinds of proteins. Recent studies have established that the free amino acid form of 3-nitrotyrosine induces cytotoxity and growth inhibition and alters the cellular function in cultured cells. The aim of this study was to evaluate whether 3-nitrotyrosine could affect tissue remodelling in fibroblasts. To accomplish this, human fetal lung fibroblasts (HFL-1) were used to assess the fibroblast-mediated contraction of floating gels and chemotaxis towards fibronectin. In addition, the ability of fibroblasts to release fibronectin, transforming growth factor (TGF)-beta1, fibronectin and vascular endothelial growth factor (VEGF) was assessed. 3-Nitrotyrosine significantly inhibited gel contraction (p<0.01) compared with control and this inhibition was abolished by nitric oxide synthase (NOS) inhibitor. 3-Nitrotyrosine did not affect TGF-beta1 and VEGF but significantly decreased fibronectin release (p<0.01) into the media. 3-Nitrotyrosine significantly inhibited chemotaxis towards fibronectin through suppression of alpha(5)beta(1) integrin expression (p<0.01). NOS inhibitor also reversed 3-nitrotyrosine-inhibited chemotaxis (p<0.01). Finally, 3-nitrotyrosine enhanced the expression of the inducible type of NOS (p<0.01) and nitric oxide release (p<0.01) through nuclear factor-kappaB activation. These results suggest that the free amino acid form of 3-nitrotyrosine can affect the tissue repair process by modulating nitric oxide production.
authors.affiliation: Third Dept of Internal Medicine, Wakayama Medical University School of Medicine, 811-1 Kimiidera, Wakayama, Wakayama 641-0012, Japan. sugiura@wakayama-med.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Sugiura
authors.forename: X
authors.initials: X
authors.lastname: Liu
authors.forename: T
authors.initials: T
authors.lastname: Ichikawa
authors.forename: M
authors.initials: M
authors.lastname: Ichinose
authors.forename: S I
authors.initials: SI
authors.lastname: Rennard
mesh_terms: D002460:Cell Line; D002633:Chemotaxis; D003094:Collagen / Q000378:metabolism*; D005347:Fibroblasts / Q000378:metabolism*; D005353:Fibronectins / Q000378:metabolism; D005782:Gels / Q000378:metabolism; D006801:Humans; D007249:Inflammation; D008168:Lung / Q000166:cytology; D016328:NF-kappa B / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D016212:Transforming Growth Factor beta / Q000378:metabolism; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000494:pharmacology; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
chemical_list: D005353:Fibronectins; D005782:Gels; D016328:NF-kappa B; D016212:Transforming Growth Factor beta; D042461:Vascular Endothelial Growth Factor A; D009569:Nitric Oxide; C002744:3-nitrotyrosine; D014443:Tyrosine; D003094:Collagen; D019001:Nitric Oxide Synthase