Study of thiobarbituric reactive substances and total reduced glutathione as indices of oxidative stress in chronic smokers with and without chronic obstructive pulmonary disease.
BACKGROUND
The imbalance between oxidants and antioxidants is thought to play an important role in the pathogenesis of chronic obstructive pulmonary disease (COPD).


METHODS
Biomarkers of lipid oxidation such as thiobarbituric reactive substances (TBARs), total reduced glutathione (GSH) were estimated in chronic smokers with and without COPD, and non-smokers.


RESULTS
The following subjects (all males) were studied: (i) chronic smokers (32.5 +/- 8.6 pack years) with stable COPD (n = 20; mean age 47.2 +/- 7.8 years); (ii) chronic smokers (6.3 +/- 1.9 pack years) without COPD (n = 20; mean age 35.3 +/- 4.5 years); and (iii) non-smokers (n = 20; mean age 37.5 +/- 5.5 years). The mean TBARs levels (nmol of malondialdehyde per ml of plasma) were higher among smokers with COPD (5.72 +/- 1.02) when compared with smokers without COPD (4.85 +/- 0.97) and non-smokers (2.58 +/- 0.56) (p < 0.001). The mean GSH levels (micromol/mg of protein) were significantly higher in non-smokers (0.163 +/- 0.113) compared to smokers with COPD (0.083 +/- 0.05) and those without COPD (0.050 +/- 0.051) (p < 0.001). There was no statistically significant difference in the plasma GSH levels among smokers with and without COPD (p > 0.05).


CONCLUSIONS
Our observations demonstrate increased lipid peroxidation because of oxidative stress due to smoking.
Premanand
R
R
Department of Tuberculosis and Chest Diseases, Division of Pulmonary and Critical Care Medicine, Sri Venkateswara Institute of Medical Sciences, Tirupati, Andhra Pradesh, India. prema2@sancharnet.in
Kumar
Santhosh
S
Mohan
Alladi
A
D000328:Adult; D016022:Case-Control Studies; D005978:Glutathione / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress / Q000502:physiology*; D029424:Pulmonary Disease, Chronic Obstructive / Q000097:blood*; D012907:Smoking / Q000097:blood*; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism*
D017392:Thiobarbituric Acid Reactive Substances; D005978:Glutathione