A study finds that exposure to radiation of the type anticipated in interplanetary space can affect intestinal epithelial cell function. Ionizing radiation is hazardous to astronauts, particularly the energetic heavy ions predicted to bombard Mars-bound astronauts. Kamal Datta and colleagues investigated the effects of energetic heavy ions on the gastrointestinal (GI) tract by exposing mice to a low dose of iron (56Fe) radiation and using the small intestine as a model system. Intestinal epithelial cell migration, essential for maintaining physiologic function and preventing pathologic processes, decreased following 56Fe exposure, relative to gamma-ray-exposed and control samples. Signaling pathways involved in key cellular processes, such as cell-cell and cell-extracellular matrix interactions and proliferation required for coordinated cell migration, were perturbed. The authors provide evidence that 56Fe can trigger senescent cells in the crypt region and that some of these cells can secrete inflammatory factors affecting cell migration. The effects of the radiation on the intestinal cells persisted 1 year after exposure. According to the authors, the results suggest the potential adverse impacts of long-duration space missions on astronaut GI function and health.
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Article #18-07522: "Space radiation triggers persistent stress response, increases senescent signaling, and decreases cell migration in mouse intestine," by Santosh Kumar, Shubhankar Suman, Albert Fornace, and Kamal Datta.
MEDIA CONTACT: Kamal Datta, Georgetown University, Washington, DC; tel: 202-687-7956; e-mail: kd257@georgetown.edu
Proceedings of the National Academy of Sciences