Ozone causes lipid peroxidation but little antioxidant depletion in exercising and nonexercising hamsters.
Long, Nancy C., Jung Suh, Jason D. Morrow, Robert H. Schiestl, G. G. Krishna Murthy, Joseph D. Brain, and Balz Frei.
1Physiology Program and 4Department of Cancer Cell Biology, Harvard School of Public Health, Boston, Massachusetts 02115; 2Linus Pauling Institute, Oregon State University, Corvallis, Oregon 97331; and 3Departments of Pharmacology and Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee 37232
APStracts 8:0336A, 2001.
Ozone (O3), a major component of urban air pollution, is a strong oxidizing agent that can cause lung injury and inflammation. In the present study, we investigated the effect of inhalation of O3 on levels of F2-isoprostanes in bronchoalveolar lavage fluid (BALF) and on levels of antioxidants in the BALF and plasma of hamsters. Because antioxidants, including urate, ascorbate, GSH, and vitamin E, defend the lungs by reacting with oxidizing agents, we expected to find a decrease in antioxidant levels after O3 exposure. Similarly, we expected an increase in the levels of F2-isoprostanes, which are lipid peroxidation products. Exposure to 1.0 or 3.0 parts/million (ppm) O3 for 6 h resulted in an increase in BALF neutrophil numbers, an indicator of acute inflammation, as well as elevation of BALF F2-isoprostanes. The higher dose of O3 caused an increase in the BALF level of urate and a decrease in the plasma level of ascorbate, but 1.0 ppm O3 had no effect on BALF or plasma antioxidant levels. Exposure to 0.12 ppm O3 had no effect on BALF neutrophils or F2-isoprostanes nor on BALF and plasma antioxidants. We also investigated the effect of O3 exposure of hamsters during exercise on F2-isoprostane and antioxidant levels. We found that exposure to 1.0 ppm O3 during 1 h of exercise on a laddermill increased BALF levels of F2-isoprostanes but had no effect on BALF neutrophils or on BALF and plasma antioxidants. These results indicate that O3 induces inflammation and biomolecule oxidation in the lungs, whereas extracellular antioxidant levels are relatively unchanged.
Received 3 August 1999; accepted in final form 25 May 2001
APS Manuscript Number A586-9.
Article publication pending J Appl Physiol
ISSN 1080-4757 Copyright 2001 The American Physiological Society.
Published in APStracts on 29 June 2001