Objective The apoptosis and DNA damage of thymus cells in mice with total body irradiation of 6 Gy were investigated to determine the effect of hydrogen-rich water on reactive oxygen species(ROS).

Methods A total of 15 mice were divided into three groups, namely, un-irradiated control group, 6 Gy irradiation group, and 6 Gy+hydrogen-rich water group. Up to 0.5 ml of hydrogen-rich water was administered to the mice in 6 Gy+hydrogen-rich water group 10 min before irradiation, which was provided once a day within 7 days after irradiation, and the other two groups were administered water instead. Thymus cells were collected at 4, 7, and 15 days after irradiation. Levels of ROS, apoptosis, and mean fluorescence intensity(MFI) of phosphorylated histone H2AX(γ-H2AX) were detected by flow cytometry.

Results ROS levels, early(Annexin V-positive and propidium iodide(PI)-negative) and late apoptotic(Annexin V-positive and PI-positive) cells, and MFI of γ-H2AX increased in the thymus of mice irradiated with 6 Gy compared with those in the un-irradiated control group. By contrast, the levels of ROS, apoptotic cells, and MFI of γ-H2AX significantly declined in the thymus of mice administered with 6 Gy + hydrogen-rich water compared with those in the irradiated mice.

Conclusion Hydrogen-rich water exerted a promising protective effect on radiation-induced thymus injury. Therefore, hydrogen-rich water is a potential radioprotective agent.