Increased oxidative stress and altered levels of antioxidants in asthma.
BACKGROUND
Reactive oxygen species might play an important role in the modulation of airway inflammation. There is evidence of an oxidant-antioxidant imbalance in asthma. Although several oxidants and antioxidants are likely to be involved, alterations in only limited parameters have been studied in isolation.


OBJECTIVE
We investigated changes in a wide range of oxidants and antioxidants to create a comprehensive picture of oxidant-antioxidant imbalance.


METHODS
In the peripheral blood of 38 patients with bronchial asthma and 23 control subjects, oxidative stress was measured in terms of superoxide anion generation by leukocytes, lipid peroxidation products, total nitrates and nitrites, total protein carbonyls, and total protein sulfhydrils in plasma. Antioxidant status was evaluated by measuring red blood cell superoxide dismutase and catalase activity, total blood glutathione, and glutathione peroxidase activity in red blood cells and leukocytes and total antioxidant capacity in plasma.


RESULTS
Asthmatic patients showed increased superoxide generation from leukocytes, increased total nitrites and nitrates, increased protein carbonyls, and increased lipid peroxidation products and decreased protein sulfhydrils in plasma, indicating increased oxidative stress. They also showed increased superoxide dismutase activity in red blood cells and increased total blood glutathione and decreased glutathione peroxidase activity in red blood cells and leukocytes. Red blood cell catalase activity and the total antioxidant capacity of plasma were not altered.


CONCLUSIONS
There are alterations in a wide array of oxidants and antioxidants, with balance shifting toward increased oxidative stress in asthma. Therapeutic augmentation of the antioxidant defenses might be beneficial.
Nadeem
Ahmad
A
Department of Biochemistry, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India.
Chhabra
Sunil K
SK
Masood
Anbrin
A
Raj
Hanumanthrao G
HG
D000293:Adolescent; D000328:Adult; D000975:Antioxidants / Q000378:metabolism*; D001249:Asthma / Q000378:metabolism*; D004912:Erythrocytes / Q000201:enzymology; D005260:Female; D006801:Humans; D007962:Leukocytes / Q000378:metabolism; D008054:Lipid Peroxides / Q000097:blood; D008297:Male; D009566:Nitrates / Q000097:blood; D009573:Nitrites / Q000097:blood; D018384:Oxidative Stress / Q000502:physiology*; D013482:Superoxide Dismutase / Q000097:blood; D013481:Superoxides / Q000097:blood; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism
D000975:Antioxidants; D008054:Lipid Peroxides; D009566:Nitrates; D009573:Nitrites; D017392:Thiobarbituric Acid Reactive Substances; D013481:Superoxides; D013482:Superoxide Dismutase