Introduction: nicotine itself is not classified as a carcinogen, but there is growing evidence that it may have genotoxic potential which has been a point of research interest.
Objectives: The present study was designed specifically to investigate the possible genotoxic effect of nicotine in adult male albino rats and to assess the probable protective role of green tea (GTE) and N-acetyl cysteine (NAC).
Material and methods: The study was carried out for four weeks on 30 adult male albino rats that were randomly divided into 6 equal groups. Group I: Rats received 3ml of distilled water orally via gastric gavage. Group II: received GTE in a dose of 150 mg/kg body weight dissolved in 3 ml distilled water) orally via an orogastric tube. Group III: took NAC dissolved in warm distilled water in a dose of 150 mg/kg daily orally through orogastric intubation. Group IV: received nicotine S.C. injection in a dose of 0.4 mg/100 gm body weight/day. Group V: received S.C nicotine in a dose of 0.4 mg/100 gm body weight/day with concomitant administration of aqueous GTE (NT + GTE). Group VI: received S.C. nicotine in a dose of 0.4 mg/100 gm body weight/day with concomitant administration of NAC (NT + NAC). After 28 days, the animals were sacrificed and blood samples were obtained. RAPD analysis was done and markers of oxidative stress as Malondialdehyde (MDA), total antioxidant capacity (TAOC) and reduced glutathione (GSH) were also assessed. Results: Biochemical assays showed a significant decrease in serum GSH, total antioxidant capacity in the nicotine-treated group than both protected group. On contrary, a significant increase in serum MDA was recorded in the nicotine-treated group than protected groups. RAPD analysis in the nicotine-treated rats revealed evident profile changes, while no change in DNA banding pattern was detected if simultaneous administration of either GTE or NAC together with nicotine.
Conclusion: These results suggest that nicotine induces oxidative stress in rats as well as a genotoxic effect; these effects could be prevented by the administration of either NAC or GTE.