The effects of genistein supplemented before or after irradiation on DNA injury in human lymphocytes in vitro

Abstract Purpose. The study aimed at the investigation if application of genistein (GEN) at different time prior or past irradiation may avert or reduce the induced by irradiation injury of DNA in human lymphocytes. Materials and Methods. The isolated lymphocytes were exposed to X-irradiation (0.5; 1 Gy). GEN (1 µM/ml; 10 µM/ml) was appended to attempts at various times prior or past irradiation (1 h prior, immediately prior, immediately past, 1 h past). We joined each X-rays dose with each GEN dose. After 1h of incubation DNA damages were examined using Comet assay. Results. Combination of 1 µM/ml of GEN given 1 h before irradiation with low or high dose markedly decreased induced by irradiation DNA injury. Higher dose of GEN applied immediately before or after irradiation markedly extended the frequency of DNA injury generated by irradiation. The result of application 1 µM/ml GEN 1 h after irradiation was not significantly different compared to control. The effect of 1 Gy + 10 µM/ml GEN was not significantly lower compared to each agent alone. Conclusions. Only a very low concentration of GEN was applied before irradiation, it may be considered as a potential radiomitigator/radioprotector. High doses of GEN work as a radiosentitizer and may potent the effects of radiotherapy.