The interrelationship between markers of inflammation and oxidative stress in chronic obstructive pulmonary disease: modulation by inhaled steroids and antioxidant

SummaryBackground: Chronic obstructive pulmonary disease (COPD) is accompanied by both airway and systemic inflammation and by oxidative stress. This study aimed to characterise the relationship between oxidative stress and inflammatory components in induced sputum and blood.Material & methods: We studied blood and sputum samples from stable COPD patients (mean FEV1 60.5±7.5% predicted) at baseline (no treatment) and after 10 weeks treatment with either inhaled steroid, fluticasone propionate (FP) (1000μg/d) or 10 weeks treatment with N-acetylcysteine (600mg/d) (NAC). We assessed the inflammatory markers (IL-8, ECP, sICAM-1, NE) in sputum and serum and we compared them with blood markers of oxidative stress (SOD, GPx, TEAC, albumin, vitamin E and A).Results: At baseline blood sICAM-1 correlated with IL-8 levels (P<0.01, r=0.62) and negatively with GPx (P<0.01, r=-0.63) and with TEAC (P<0.05, r=-0.53). TEAC correlated positively with GPx (P