Effect of Allergen Inhalation on Airway Oxidant Stress, Using Exhaled Breath Condensate 8-Isoprostane, in Mild Asthma

Abstract

Objective. Exhaled breath condensate (EBC) 8-isoprostane concentrations are increased in asthma, but it is not known if they acutely change following bronchoprovocation. The objective of this study was to evaluate EBC 8-isoprostane concentrations following allergen-induced bronchoprovocation in asthma. Methods. This comparison study included eight mild atopic asthmatics and six controls. Asthmatics were challenged with inhaled specific allergen, methacholine, and irrelevant allergen in random order. Controls were challenged with irrelevant allergen. EBCs collected at 0, 3, 6, 9, and 23 hours by the R-tube method were measured for 8-isoprostanes by ELISA technique. Repeated measures ANOVA technique was used for analysis. Results. EBC 8-isoprostane concentrations did not change following any inhalational challenge, as compared to baseline, in either asthmatics or controls. Conclusions. EBC 8-isoprostane concentrations do not acutely change following bronchoprovocation in subjects with mild asthma.

• 8-isoprostanes
• allergen bronchoprovocation
• asthma
• exhaled breath condensate
• oxidant stress