Progressive exercise training protects bone marrow stem cells from radiation‐induced damage

Exercise training is known to induce an adaptive response in numerous tissues, however, the effects of exercise training on bone marrow stem cells (BMSC) is unknown. The purpose of this study was to determine if exercise training produced adaptations in BMSC and if this adaptive response could protect against subsequent high levels of ROS. C57Bl/6 mice were divided into the following groups (n=6 per group): treadmill running (EX), treadmill running and low dose radiation (ExLDR), and control (CON). Following 10 weeks of intervention half the mice in each group were exposed to a high dose radiation (HDR) challenge. Exercise training did not affect the basal number of double strand breaks (DSB) as determined by Gamma H2AX foci, but resulted in significantly fewer DSB in response to HDR, in vitro . Furthermore, exercise training significantly decreased both the basal number of micronucleated reticulocytes (MN‐RET) as well as the number of MN‐RET in response to HDR, in vivo . Interestingly, exercise was able to prevent the increase in basal MN‐RET in the mice exposed to 10 weeks of LDR. In conclusion, progressive exercise training was sufficient to protect BMSC from high doses of radiation. This research was funded by US DOE, Low Dose Research Program (DE‐FG02‐07ER64343) and NSERC.