Lipid peroxidation and 5-lipoxygenase activity in Chronic Obstructive Pulmonary Disease subjects

We studied the urinary excretion of the isoprostane 8-iso-Prostaglandin F2α, as an index of in vivo oxidant stress, and the production of leukotriene B4 (LTB4) by neutrophils in chronic obstructive pulmonary disease (COPD) and normal subjects. Overnight urinary excretion of the isoprostane resulted significantly higher in COPD patients than in controls, and LTB4 production by challenge of neutrophils obtained from COPD patients also resulted significantly higher than that observed in control neutrophils. Treatment with a standardized polyphenol extract caused a significant decrease in isoprostane excretion, accompanied by statistically significant increase of partial pressure of arterial oxygen. 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 COPD subjects is paralleled by the increased ability of neutrophil to synthesize the chemotactic factor LTB4, and may ultimately contribute to the infiltration/activation of neutrophils into the airways of COPD subjects. Antioxidant treatment in COPD subjects 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 partial pressure of arterial oxygen and FEV1.