Background: To study the radioprotective effects of flavonoids from Rosa roxburghii Tratt (FRT). Materialsand Methods: The radioprotective effects of FRT were investigated by examining cell viability, 30-day survivalof mice and the number of colony-forming units in spleen (CFU-S) after total-body 60Co irradiation. Results:The survival rates of irradiated cells gradually increased with increasing concentrations of FRT. The survivalrate was the highest at 87% with a concentration of 30 μg/mL. Pretreatment with FRT was needed to realize itsradioprotective activity in mice at the dose of 60 mg/kg. With the increasing doses of 30 mg/kg, 60 mg/kg and120 mg/kg, the numbers of CFU-S increased, and were significantly different compared with the control group. Conclusions: Pretreatment with FRT prior to irradiation resulted in significantly higher cell survival at 24 hafter 5 Gy radiation, increased 30-day survival in mice after exposure to a potentially lethal dose of 8 Gy, andresulted in a higher number of CFU-S in mice after exposure to a dose of 6 Gy. These results collectively indicatethat FRT is an effective radioprotective agent.
)