Chemoprevention of DNA damage in bronchoalveolar lavage cells of mice exposed to cigarette smoke

Cigarette smoke is the major risk factor for lung cancer and a variety of chronic degenerative diseases. We tested the ability of the glucocorticoid budesonide and of the natural agent phenethyl isothiocyanate (PEITC) to inhibit DNA damage in bronchoalveolar lavage cells (BAL) of CD–1 mice exposed to environmental cigarette smoke (ECS). A total of 197 mice were divided into following experimental groups: (A) untreated (sham); (B) ECS; (C) ECS þPEITC; (D) ECS þ budesonide. Exposure to ECS started within 12 h after birth and continued throughout the weaning period and for 2 additional weeks after weaning, for a total of 7 weeks. After treatment, the mice were sacrificed and subjected to BAL in order to evaluate DNA damage in BAL cells by using the alkaline–halo test. DNA damage was significantly increased in ECS exposed mice vs. Sham (3.3-fold). Both PEITC (2.4-fold) and budesonide (2.0- fold) significantly attenuated ECS-induced DNA damage. In conclusion, the analysis of sentinel cells collected by BAL showed that the investigated agents, which are among the most promising chemopreventive agents, are able to revert the DNA damage produced by passive exposure to cigarette smoke.