CIGARETTE-SMOKING INDUCES AN INCREASE IN OXIDATIVE DNA-DAMAGE, 8-HYDROXYDEOXYGUANOSINE, IN A CENTRAL SITE OF THE HUMAN LUNG

To evaluate the effect of cigarette smoking on oxidative stress in lun g tissues, we compared the levels of a type of oxidative DNA damage, 8 -hydroxydeoxyguanosine (8-OH-dG), in tissue obtained from the central sites of lungs from 14 current smokers, seven ex-smokers and nine nons mokers, The mean level of 8-OH-dG in the lung tissues from smokers was 1.43-fold higher than that of the nonsmokers (the difference was stat istically significant, P = 0.0262). A positive correlation between the 8-OH-dG levels in normal lung tissues and the Brinkman index was obta ined from smokers and ex-smokers (r = 0.525; P = 0.0134). A positive c orrelation was also obtained for the 8-OH-dG levels in normal lung tis sues and the number of cigarettes smoked per day (r = 0.436; P = 0.013 2). These results suggest that oxidative DNA damage is induced in lung DNA by cigarette smoking.