DNA damage and repair capacity by comet assay in lymphocytes of white-collar active smokers and passive smokers (non- and ex-smokers) at workplace.
The comet assay has been widely used to quantify DNA damage in isolated lymphocytes from subjects exposed to several environmental or occupational substances, especially for estimation of oxidative damage in the DNA, which is well-known to be induced by tobacco smoke. Passive smoking or environmental tobacco smoke (ETS) has been included among those substances that cause cancer with sufficient evidence in humans. In this study, we analyzed, by the alkaline version of comet assay, the lymphocyte DNA damage of white-collar active smokers and non- and ex-smokers exposed to ETS at the workplace. We investigated basal DNA damage, DNA oxidation by formamidopyrimidine glycosylase (Fpg), the repair capacity H2O2-induced DNA damage by kinetics studies and lymphocyte GSH levels, the major intracellular defense against exogenous oxidative stress imposed by cigarette smoking. Our results indicated high basal DNA damage with clear significant correlations with urinary nicotine and cotinine, number of cigarettes/day, and an inverse significant correlation with GSH cellular content in active smokers. Significant Fpg-sensitive sites were found in smokers (> 85%), considerably high but not significant in passive non- and ex-smokers (> 51% and 37%, respectively). The DNA repair capacity had seriously decreased in non-smokers > smokers > ex-smokers, while the same damage was repaired in a short time in never smokers.
Fracasso
Maria Enrica
ME
Department of Medicine and Public Health, Section of Pharmacology, University of Verona, Policlinico GB Rossi, P.le Scuro 10, 37134 Verona, Italy. mariaenrica.fracasso@univr.it
Doria
Denise
D
Franceschetti
Paola
P
Perbellini
Luigi
L
Romeo
Luciano
L
D000328:Adult; D000395:Air Pollutants, Occupational / Q000009:adverse effects*; D015415:Biomarkers / Q000652:urine; D020552:Comet Assay; D003367:Cotinine / Q000652:urine; D004249:DNA Damage; D004260:DNA Repair; D043382:DNA-Formamidopyrimidine Glycosylase / Q000494:pharmacology; D005260:Female; D005978:Glutathione / Q000378:metabolism; D006801:Humans; D006861:Hydrogen Peroxide / Q000633:toxicity; D008214:Lymphocytes / Q000187:drug effects; D008297:Male; D009538:Nicotine / Q000652:urine; D016273:Occupational Exposure / Q000009:adverse effects*; D012907:Smoking / Q000009:adverse effects* / Q000378:metabolism; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*; D017132:Workplace
D000395:Air Pollutants, Occupational; D015415:Biomarkers; D014028:Tobacco Smoke Pollution; D009538:Nicotine; D006861:Hydrogen Peroxide; D043382:DNA-Formamidopyrimidine Glycosylase; D005978:Glutathione; D003367:Cotinine