Hydrogen peroxide and nitrite reduction in exhaled breath condensate of COPD patients.

Chronic obstructive pulmonary disease (COPD) is predominantly the result of years of cigarette smoking. Increased oxidative stress in COPD derives from the increased burden of inhaled oxidants (cigarette smoke), air pollution and the increase in reactive oxygen and nitrogen species (ROS and RNS), generated by some inflammatory, immune, and structural airways cells. In view of the lack of therapy that might inhibit the progress of the disease, there is an urgent need for a successful therapeutic approach. Apocynin is a molecule inhibiting activation of NADPH oxidase - enzyme generating ROS and RNS precursor. Thus, our aim was to analyze apocynin influence on hydrogen peroxide and nitrite concentrations in EBC of COPD patients. Apocynin reduced concentration of H(2)O(2) in COPD patients 60 and 120 min after apocynin inhalation, in comparison to placebo (0.43 μM vs. 0.59 μM, and 0.4 μM vs. 0.59 μM respectively, p < 0.05). Moreover, apocynin decreased NO(2)(-) ions concentration in airways of COPD patients after apocynin nebulization (3.97 μM vs. 4.48 μM after 30 min, 3.82 μM vs. 4.48 μM after 60 min, and 3.76 μM vs. 4.48 μM after 30 min respectively, p < 0.05). No adverse effects have been observed. The results suggest that apocynin might be considered as anti-inflammatory agent, and, possibly used in therapy of COPD.