Decreased copper, zinc superoxide dismutase activity in asthmatic airway epithelium: correction by inhaled corticosteroid in vivo. Raeve, Hilde R. De, Frederic B. J. M. Thunnissen[tilde]n, F. Takao Kaneko, Fuhua H. Guo, Marc Lewis, Mani S. Kavuru, Michelle Secic, Mary Jane Thomassen, and Serpil C. Erzurum. Departments of Pulmonary and Critical Care Medicine, Cancer Biology, Biostatistics and Epidemiology, Cleveland Clinic Foundation, Cleveland, Ohio 44195, Institutional affiliation: Department of Pathology, University of Limburg, Maastricht, The Netherlands
APStracts 3:0184L, 1996.
To investigate the antioxidant response of respiratory epithelium to the chronic airway inflammation in asthma, the major intracellular antioxidants [Cu, Zn and Mn superoxide dismutases (SOD), catalase, glutathione peroxidase] were quantitated in bronchial epithelial cells of healthy control and asthmatic individuals. While catalase and glutathione peroxidase in bronchial epithelium of asthmatics were similar to control, SOD activity in asthmatics not on inhaled corticosteroid (-CS) was lower than asthmatics on inhaled corticosteroid (+CS) and controls. Investigation of MnSOD and CuZnSOD activities revealed that the lower SOD activity in asthmatics -CS was due to decreased CuZnSOD activity. However, MnSOD and CuZnSOD mRNA and protein levels were similar among asthmatics -CS, +CS and controls. Importantly, CuZnSOD specific activity in asthmatics -CS was decreased in comparison to control and asthmatic +CS. Further, in paired comparisons of asthmatics -CS and +CS, inhaled corticosteroids resulted in normalization of bronchial epithelial CuZnSOD specific activity. These findings suggest loss of CuZnSOD activity in asthma is related to inflammation, perhaps through oxidant inactivation of CuZnSOD protein. 

Received 1 April 1996; accepted in final form 10 September 1996.
APS Manuscript Number L109-6.
Article publication pending Am. J. Physiol. (Lung Cell. Mol.
Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 5 November 1996