title: Increased serum levels of nitrotyrosine, a marker for peroxynitrite production, in systemic sclerosis.
abstract: OBJECTIVE
  To determine serum levels of nitrotyrosine (NT), an end product of peroxynitrite (ONOO-), and its clinical association in patients with systemic sclerosis (SSc).
  
  
  METHODS
  Serum NT levels from 25 patients with limited cutaneous SSc (lSSc) and 34 patients with diffuse cutaneous SSc (dSSc) were examined by enzyme-linked immunosorbent assay.
  
  
  RESULTS
  Serum NT levels were elevated in SSc patients compared with normal controls (n = 27), the levels being similar between lSSc and dSSc patients (P < 0.001). SSc patients with elevated NT had higher serum levels of anti- agalactosyl IgG Ab, IgG and IgA than those with normal NT levels (P < 0.05). NT levels correlated inversely with the percentage diffusion capacity for carbon monoxide (DLco) (P < 0.02, r = -0.414, n = 47).
  
  
  CONCLUSIONS
  These results suggest that ONOO- may play an important role in the clinical manifestations of SSc, especially vascular damage to the lungs, and that ONOO- may be related to immunological abnormalities in SSc.
authors.affiliation: Department of Dermatology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Shimizu
authors.forename: F
authors.initials: F
authors.lastname: Ogawa
authors.forename: E
authors.initials: E
authors.lastname: Muroi
authors.forename: T
authors.initials: T
authors.lastname: Hara
authors.forename: K
authors.initials: K
authors.lastname: Komura
authors.forename: S-J
authors.initials: SJ
authors.lastname: Bae
authors.forename: S
authors.initials: S
authors.lastname: Sato
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D002248:Carbon Monoxide / Q000378:metabolism; D016022:Case-Control Studies; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D008168:Lung / Q000098:blood supply / Q000473:pathology; D008297:Male; D008875:Middle Aged; D030421:Peroxynitrous Acid / Q000235:genetics / Q000378:metabolism*; D012595:Scleroderma, Systemic / Q000097:blood / Q000378:metabolism*; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000097:blood
chemical_list: D015415:Biomarkers; D007070:Immunoglobulin A; D007074:Immunoglobulin G; C064155:agalactosyl IGG; D030421:Peroxynitrous Acid; C002744:3-nitrotyrosine; D014443:Tyrosine; D002248:Carbon Monoxide