緊急時放射線被ばく線量推定のための尿中バイオマーカー8-Hydroxy-2’-Deoxyguanosineの検討

抄録

The exposure of radiation workers to ionizing radiation is controlled by attaching physical or chemical dose measurement devices to their body and performing regular medical examinations. In contrast, because a personal dosimeter is rarely used for the general public, it is almost impossible to perform a real-time estimation of radiation exposure. Therefore, a detailed health evaluation method in case of unexpected radiation exposure is not established. Recently, radiation biodosimetry using biogenic substances has become the area of focus, and some researchers have investigated the basics of this approach for further development with high precision. To comprehensively understand these radiation exposure phenomena, urine components, 8-Hydroxy-2’-Deoxyguanosine (8-OHdG), which can be easily extracted and is a marker of oxidative DNA damage was considered as biomarkers. Urine sample was collected after 72 h of X-ray irradiation (1.0 Gy/min) from a male mouse (C57BL/6N). The influence on bone marrow cells, due to acute radiation syndrome, was evaluated using flowcytometry. The urinary concentration of 8-OHdG was 36.5 ± 6.0 (ng/mg, normalized by creatinine), and the concentration remained similar upto 4 Gy exposure. An approximate 2.5~3.8-fold significant increase in 8-OHdG under >7 Gy exposure was observed. These results suggested that 8-OHdG are urinary biomarkers of lethal/sublethal ionizing radiation doses.