title: Quantitative assessment of protein-bound tyrosine nitration in airway secretions from patients with inflammatory airway disease.
abstract: Because reactive nitrogen species (RNS) have potent inflammatory activity, they may be involved in the inflammatory process in pulmonary diseases. We recently reported increased numbers of 3-nitrotyrosine immunopositive cells, which are evidences of RNS production, in the sputum of patients with chronic obstructive pulmonary disease (COPD) and patients with asthma compared with healthy subjects. In the present study, we attempted to quantify this protein nitration in the airways by means of high-performance liquid chromatography (HPLC) used together with an electrochemical detection system that we developed. Sputum samples were obtained from 15 stable COPD patients, 9 asthmatic patients and 7 healthy subjects by using hypertonic saline inhalation. The values for the molar ratio of protein-bound 3-nitrotyrosine/tyrosine in patients with asthma (4.31 +/- 1.13 x 10(-6), p < 0.05) and patients with COPD (3.04 +/- 0.36 x 10(-6), p < 0.01) were significantly higher than those in healthy subjects (1.37 +/- 0.19 x 10(-6)). The levels of protein-bound 3-nitrotyrosine in the airways were not significantly different in asthmatic patients and COPD patients. A significant negative correlation was found between values for protein-bound 3-nitrotyrosine/tyrosine and % FEV1 values in patients with COPD (r = -0.53, p < 0.05) but not in patients with asthma. These results suggest that our HPLC-electrochemical method is useful for quantifying RNS production in human airways. More importantly, they show that increased RNS production in the airways seems to contribute in a critical way to the pathogenesis of COPD, and that the effects of RNS in airways may differ in asthma and COPD.
authors.affiliation: Division of Respiratory and Infectious Diseases, Tohoku University Graduate School of Medicine, Sendai 980-8574, Japan. sugiura@intl.med.tohoku.ac.jp
authors.forename: Hisatoshi
authors.initials: H
authors.lastname: Sugiura
authors.forename: Masakazu
authors.initials: M
authors.lastname: Ichinose
authors.forename: Masafumi
authors.initials: M
authors.lastname: Tomaki
authors.forename: Hiromasa
authors.initials: H
authors.lastname: Ogawa
authors.forename: Akira
authors.initials: A
authors.lastname: Koarai
authors.forename: Tomomi
authors.initials: T
authors.lastname: Kitamuro
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Komaki
authors.forename: Takefumi
authors.initials: T
authors.lastname: Akita
authors.forename: Hirohito
authors.initials: H
authors.lastname: Nishino
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Okamoto
authors.forename: Takaaki
authors.initials: T
authors.lastname: Akaike
authors.forename: Toshio
authors.initials: T
authors.lastname: Hattori
mesh_terms: D000368:Aged; D001249:Asthma / Q000378:metabolism* / Q000503:physiopathology; D016022:Case-Control Studies; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004563:Electrochemistry / Q000379:methods; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000032:analysis; D011506:Proteins / Q000378:metabolism; D029424:Pulmonary Disease, Chronic Obstructive / Q000378:metabolism* / Q000503:physiopathology; D012016:Reference Values; D012680:Sensitivity and Specificity; D013183:Sputum / Q000378:metabolism*; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000032:analysis* / Q000378:metabolism
chemical_list: D011506:Proteins; D009569:Nitric Oxide; C002744:3-nitrotyrosine; D014443:Tyrosine