SUPEROXIDE ANION FORMATION AND GLUTATHIONE METABOLISM OF BLOOD IN PATIENTS WITH IDIOPATHIC PULMONARY FIBROSIS

The oxidant-antioxidant imbalance in the lower respiratory tract plays a major role in the pathogenesis in idiopathic pulmonary fibrosis (IP F), However, the systemic oxidant-antioxidant balance in the patients with IPF has not been extensively evaluated. In this study, the metabo lism of glutathione (GSH) and superoxide anion production of whole blo od were tested in 14 IPF patients and 12 normal subjects, While the to tal amount of GSH in the blood of IPF patients was not different from that of normal subjects (IPF; 22.9 +/- 4.9 mu g/ml, control; 26.1 +/- 3.7 mu g/ml), the amount of oxidized GSH (GSSG) and the ratio of GSSG to the total GSH in blood significantly increased in patients with IPF (IPF; 14.4 +/- 3.5%, control; 7.0 +/- 1.7%, P < 0.01), indicating tha t the glutathione redox cycle may be impaired in IPF. The production a nd generation of superoxide anions by blood were significantly greater in IPF than in normal subjects. The level of superoxide anion product ion was correlated with the GSSG/GSH ratio. These results indicate tha t IPF patients exhibit an impaired GSH metabolism with an increased ox idant formation of blood. (C) 1995 Academic Press, Inc.