Lycopene: An antioxidant and radioprotector against γ-radiation-induced cellular damages in cultured human lymphocytes

The present study aimed to evaluate the radioprotective effect of lycopene, a naturally occurring dietary carotenoid on gamma-radiation-induced toxicity. The cellular changes were estimated by using lipid peroxidative indices like thiobarbituric acid reactive substances (TBARS), hydroperoxides (HP), the antioxidants superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and reduced glutathione (GSH). The DNA damage was analyzed by cytokinesis blocked micronucleus assay (CBMN), dicentric aberration (DC) and translocation frequency. The gamma-radiation at different doses (1, 2 and 4 Gy) resulted in a significant increase in the number of micronuclei (MN), DC, translocation frequency, TBARS and HP level, whereas the levels of GSH and antioxidant enzymes were significantly decreased when compared with normal control. The maximum damage to lymphocytes was observed at 4 Gy irradiation. Lycopene pretreatment (1, 5 and 10 mu g/ml) significantly decreased the frequency of MN, DC and translocation when compared with gamma-radiation control. The levels of TBARS, HP were also decreased and activities of SOD, CAT and GPx were significantly increased along with GSH levels when compared with gamma-radiation control. The dose of 5 mu g/ml of lycopene was found to be more effective than the other two doses. Thus, our result shows that pretreatment with lycopene offers protection to normal lymphocytes against gamma-radiation-induced cellular damage. (C) 2009 Elsevier Ireland Ltd. All rights reserved.