Feeding Drosophila highly radioresistant fungi improves survival and gut morphology following acute gamma radiation exposure.

Diverse fungi have been historically vital reservoirs of drug discovery, providing life-saving pharmaceuticals. Many species of fungi, yeasts in particular, are highly resistant to radiation, with their cellular contents potentially conferring dietary radioresistance. We developed a model to test whether feeding two highly radioresistant fungi, and , could improve fly lifespan and gut morphology after acute irradiation. We constructed a dosimetry curve for the lifespan response of males and females to irradiation and found dose-dependent and sex-specific effects on lifespan. We also determined that the sex-specific response to irradiation correlated with nuclear morphology defects in the gut, with the more radiosensitive males displaying increased midgut cellular holes and aberrant nuclear morphology. To determine if feeding and before irradiation could improve survival and gut morphology, we first exclusively fed males and females each fungus and observed that they tolerated the diet well. Using these methods, we found that only two days of prefeeding increased male lifespan, but not female, after irradiation, and improved nuclear morphology in the gut. However, dietary was not protective. Overall, this study identified a highly radioresistant dietary fungus, , as effective for extending male lifespan and improving gut morphology following irradiation. Since the gut is particularly sensitive to the effects of irradiation, this fungus indicates a potential therapeutic for patients undergoing radiotherapy. Furthermore, this method could identify additional radioresistant fungi that protect the gut from radiation injury.