Oxygen metabolite detoxifying enzyme levels in bleomycin-induced fibrotic lungs.
The activities of three enzymes cytosolic superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSHP), and malonyldialdehyde (MDA), a by-product of lipid peroxidation, were determined in whole lungs of normal and bleomycin-treated rats. Two days after bleomycin treatment total lung SOD, CAT, and GSHP activities were significantly (p less than .025) depressed between 15 and 25%. The activities of all three enzymes increased 4 days after bleomycin treatment with only SOD significantly increased at days 4 and 7. Total lung CAT activity remained near normal levels while GSHP activity increased only at day 28 (160.5%, p less than .01) indicating a specificity of the response of lung SOD and GSHP levels. Total lung MDA levels were increased by 17% at 2 and 4 days (p less than .05) after bleomycin treatment, and returned to normal levels at 7 and 28 days. These data suggest that impairment of the lung's ability to detoxify O2 metabolites may play an important role in the development of bleomycin-induced pulmonary fibrosis.
Fantone
J C
JC
Department of Pathology, University of Michigan Medical School, Ann Arbor 48109-0602.
Phan
S H
SH
D000818:Animals; D000975:Antioxidants / Q000032:analysis*; D001761:Bleomycin; D002374:Catalase / Q000378:metabolism*; D003600:Cytosol / Q000201:enzymology; D005609:Free Radicals; D005979:Glutathione Peroxidase / Q000378:metabolism*; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D011658:Pulmonary Fibrosis / Q000139:chemically induced / Q000201:enzymology*; D051381:Rats; D011916:Rats, Inbred F344; D013482:Superoxide Dismutase / Q000378:metabolism*
D000975:Antioxidants; D005609:Free Radicals; D001761:Bleomycin; D008315:Malondialdehyde; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase