Increased exhaled 8-isoprostane in childhood asthma

Chest. 2003 Jul;124(1):25-31. doi: 10.1378/chest.124.1.25.


Study objective: To quantify lung oxidative stress in asthmatic children by measuring concentrations of 8-isoprostane, a marker of oxidative stress, in exhaled breath condensate (EBC), which is a noninvasive method of sampling airway secretions. Secondary objectives were as follows: (1) to measure levels of exhaled prostaglandin (PG) E(2), since impaired PGE(2) production has been implicated in the pathogenesis of asthma in adults; and (2) to measure levels of fractional exhaled nitric oxide (FeNO), which is a marker of airway inflammation.

Design: Single-center, cross-sectional study.

Patients: Twelve healthy children, 12 steroid-naïve asthmatic children, and 30 children in stable condition with mild-to-moderate persistent asthma who were being treated with inhaled corticosteroids (ICSs) [average dose, 300 micro g per day] were studied.

Interventions: Subjects attended the outpatient clinic on one occasion for the collection of EBC and FeNO measurements.

Measurements and results: 8-Isoprostane and PGE(2) concentrations in EBC were measured with specific radioimmunoassays. FeNO was measured online by a chemiluminescence analyzer. 8-Isoprostane was detectable in the EBC of healthy children (mean [+/- SEM], 34.2 +/- 4.5 pg/mL), and its concentrations were increased in both steroid-naïve asthmatic children (mean, 56.4 +/- 7.7 pg/mL; p < 0.01) and steroid-treated asthmatic children (mean, 47.2 +/- 2.3 pg/mL; p < 0.05). There was no difference in exhaled 8-isoprostane concentrations between the two groups of asthmatic children (p = 0.14). By contrast, exhaled PGE(2) concentrations were similar among the three study groups (p = 0.56). FeNO levels were higher in steroid-naïve children with asthma (49.2 +/- 9.6 parts per billion [ppb]; p < 0.05) and, to a lesser extent, in steroid-treated asthmatic children (37.8 +/- 6.6 ppb; p < 0.05) compared with healthy children (15.2 +/- 1.7 ppb).

Conclusions: Lung oxidative stress is increased in children who are in stable condition with asthma, as reflected by increased exhaled 8-isoprostane concentrations. This increase seems to be relatively resistant to treatment with ICSs. Decreased PGE(2) lung production is unlikely to play a pathophysiologic role in childhood asthma.

MeSH terms

  • Adolescent
  • Anti-Inflammatory Agents / therapeutic use
  • Asthma / diagnosis
  • Asthma / drug therapy
  • Asthma / metabolism*
  • Breath Tests
  • Child
  • Child, Preschool
  • Cross-Sectional Studies
  • Dinoprost* / analogs & derivatives*
  • Dinoprostone / metabolism
  • F2-Isoprostanes / metabolism*
  • Female
  • Forced Expiratory Volume
  • Humans
  • Luminescent Measurements
  • Male
  • Nitric Oxide / metabolism
  • Oxidative Stress*
  • Radioimmunoassay
  • Respiratory Function Tests
  • Steroids


  • Anti-Inflammatory Agents
  • F2-Isoprostanes
  • Steroids
  • 8-epi-prostaglandin F2alpha
  • Nitric Oxide
  • Dinoprost
  • Dinoprostone