Protective Effects of Lycopene on the γ-radiation Induced Chromosomal Damage and Cell Killing in Cultured Human Fibroblast Cells

Lycopene is one of the most potent antioxidants. It is a red, fat soluble pigment found in certain plants and microorganisms. Several studies have demonstrated the ability of lycopene to protect the cells from ionizing radiation induced damage, however, the mechanisms involved are remained to be clear. In the present study, we investigated the radioprotective effect of lycopene on γ-radiation induced cytotoxicity and genotoxicity in human cultured fibroblasts. Subjects and In irradiated groups fibroblast cells were irradiated with 1, 2 and 4Gy. In lycopene groups fibroblast cells were pretreated with different concentrations of lycopene (2, 10 and 20uM) then exposed to different doses of gamma radiation. The extent of cytotoxicity was determined by colony formation assay. The level of genotoxicity was detected by analysis of chromosmome breaks. Using colony formation assay, we observed the increase in cell killing with the increase in γ-radiation dose (1, 2 and 4Gy). Pre-treatment with lycopene (2, 10 and 20μM) restored the cell survival, suggesting that lycopene can protect the cells from killing by ionizing radiation. Similarly, lycopene significantly diminished the level of chromosome and chromatid breaks induced by gamma radiations. The maximum protection of fibroblast cells was observed at 10μM of lycopene pretreatment. Data showed that pretreatment with lycopene reduced the level of cell killing and chromosomal breaks and this protecive activity was dependent on the concentration of lycopene. Our finding indicate that lycopene protects human cells from radiation-induced genomic instability, and can reduce the cancerogenic effect of ionizing radiation.