The increased cancer risk during and after long-duration deep space missions remains a concerning late effect of space radiation exposure. Current models predict a higher probability of space radiation-induced gastrointestinal cancer incidence and mortality after a Mars mission. In the MICROBIANproject, we investigate if radiation-induced alterations in the gut microbiome can serve as biomarkers for predicting space radiation-associated health risks. This rationale is supported by numerous studies linking changes in gut microbial composition and diversity to a wide range of diseases, including colorectal cancer and central nervous system impairments.

The symbiotic relationship between the gut microbiota and the host plays also a critical role in the metabolic adaptations observed in hibernating mammals. Since hibernation, or induced synthetic torpor, has emerged as a promising strategy for deep-space exploration, largely due to its potential radioprotective aspects, we examine gut microbiome dynamics during synthetic torpor in mice. The observed changes in gut microbial communities may provide valuable insights for developing microbiome-based countermeasures to protect astronauts from space radiation damage and preserve GI homeostasis, and support overall physiological resilience during spaceflight.

Furthermore, the gut microbiome has been shown to modulate both the efficacy and toxicity of radiotherapy, underscoring its strong association with individual radiosensitivity. As a result, we are systematically characterizing radiation-induced alterations of the gut microbiome across preclinical mouse models and clinically relevant particle therapy exposures.

Contact: C. Vandevoorde (c.vandevoorde(at)gsi.de) and A. Jansen van Vuuren (A.JansenvanVuuren(@)gsi.de)