title: Smoking, COPD, and 3-nitrotyrosine levels of plasma proteins.
abstract: BACKGROUND
  Nitric oxide is a physiological regulator of endothelial function and hemodynamics. Oxidized products of nitric oxide can form nitrotyrosine, which is a marker of nitrative stress. Cigarette smoking decreases exhaled nitric oxide, and the underlying mechanism may be important in the cardiovascular toxicity of smoking. Even so, it is unclear if this effect results from decreased nitric oxide production or increased oxidative degradation of nitric oxide to reactive nitrating species. These two processes would be expected to have opposite effects on nitrotyrosine levels, a marker of nitrative stress.
  
  
  OBJECTIVE
  In this study, we evaluated associations of cigarette smoking and chronic obstructive pulmonary disease (COPD) with nitrotyrosine modifications of specific plasma proteins to gain insight into the processes regulating nitrotyrosine formation.
  
  
  METHODS
  A custom antibody microarray platform was developed to analyze the levels of 3-nitrotyrosine modifications on 24 proteins in plasma. In a cross-sectional study, plasma samples from 458 individuals were analyzed.
  
  
  RESULTS
  Average nitrotyrosine levels in plasma proteins were consistently lower in smokers and former smokers than in never smokers but increased in smokers with COPD compared with smokers who had normal lung-function tests.
  
  
  CONCLUSIONS
  Smoking is associated with a broad decrease in 3-nitrotyrosine levels of plasma proteins, consistent with an inhibitory effect of cigarette smoke on endothelial nitric oxide production. In contrast, we observed higher nitrotyrosine levels in smokers with COPD than in smokers without COPD. This finding is consistent with increased nitration associated with inflammatory processes. This study provides insight into a mechanism through which smoking could induce endothelial dysfunction and increase the risk of cardiovascular disease.
authors.affiliation: Cell Biology and Biochemistry, Pacific Northwest National Laboratory, Richland, Washington 99354, USA.
authors.forename: Hongjun
authors.initials: H
authors.lastname: Jin
authors.forename: Bobbie-Jo
authors.initials: BJ
authors.lastname: Webb-Robertson
authors.forename: Elena S
authors.initials: ES
authors.lastname: Peterson
authors.forename: Ruimin
authors.initials: R
authors.lastname: Tan
authors.forename: Diana J
authors.initials: DJ
authors.lastname: Bigelow
authors.forename: Mary Beth
authors.initials: MB
authors.lastname: Scholand
authors.forename: John R
authors.initials: JR
authors.lastname: Hoidal
authors.forename: Joel G
authors.initials: JG
authors.lastname: Pounds
authors.forename: Richard C
authors.initials: RC
authors.lastname: Zangar
mesh_terms: D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D001798:Blood Proteins / Q000032:analysis / Q000378:metabolism*; D003430:Cross-Sectional Studies; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D008875:Middle Aged; D009569:Nitric Oxide / Q000378:metabolism*; D029424:Pulmonary Disease, Chronic Obstructive / Q000097:blood / Q000378:metabolism*; D012907:Smoking / Q000009:adverse effects*; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000097:blood / Q000378:metabolism; D014589:Utah; D055815:Young Adult
chemical_list: D001798:Blood Proteins; D009569:Nitric Oxide; C002744:3-nitrotyrosine; D014443:Tyrosine