Lipid peroxidation and 5-lipoxygenase activity in chronic obstructive pulmonary disease

We studied the urinary excretion of the isoprostane 8-iso-prostaglandin F2 as an index of in vivo oxidant stress, and the production of leukotriene (LT) B4 (LTB4) by neutrophils in subjects with chronic obstructive pulmonary disease (COPD) and normal subjects. Overnight urinary excretion of the isoprostane was significantly higher in patients with COPD than in control subjects, and LTB4 production by challenge of neutrophils obtained from patients with COPD was also significantly higher than that observed in control neutrophils. Treatment with a standardized polyphenol extract caused a significant decrease in isoprostane excretion, accompanied by a statistically significant increase of PaO2. Furthermore, changes in FEV1 significantly correlated with the changes in isoprostane urinary excretion observed from enrollment to the end of treatment. The results of this study suggest that enhanced oxidative stress in subjects with COPD is paralleled by the increased ability of neutrophils to synthesize the chemotactic factor LTB4, and may ultimately contribute to the infiltration/activation of neutrophils into the airways of subjects with COPD. Antioxidant treatment in subjects with COPD is effective in reducing oxidant stress as shown by the decrease of urinary isoprostane, a reduction that correlates with the severity of the disease, as indicated by changes in PaO2 and FEV1.