In vivo Time-Dependent Radio-Protective Effect of Lycopene Against Whole-Body Gamma Radiation in Mice

Background Ionizing radiation has become an essential part of modern medicine. However, applying the effective dose of ionizing radiation is compromised by its inevitable radiation-induced damage to normal tissues. Natural products with free radical scavenging, antioxidant activities, and immune stimulatory effects offer suitable radio-protective effects. Objectives This study was designed to evaluate the in vivo radio-protective activity of lycopene, a naturally dietary carotenoid, against whole-body gamma-irradiation-induced mortality and sickness in mice. Methods In this animal experimental study, lycopene was extracted from tomato paste, characterized, and then administered to mice. Consecutively, 80 healthy adult male mice were recruited and irradiated individually, and then monitored for irradiation sickness and survival parameters. Results Pretreatment with 7 mg/kg dose of lycopene 7 days before irradiation was found to reduce the severity of symptoms of radiation sickness in a 30-day post-radiation monitoring. Lycopene treatment increased the survival rate. At the radiation dosage of 8 and 9 Gy, the difference between the survival rates of control and sample groups became significant after day 15 and 25. Lycopene was also shown to have a protective effect on white blood cell count against 8 and 9 Gy gamma radiations. Conclusions Natural and exhibiting whole-body radio-protective activity, lycopene can be proposed as an effective radio-protector in healthy people who are exposed to radiation, such as radiographers, nuclear pharmacists, and radiologists.