Spaceflight affects mitochondria

Spaceflight is known to affect human physiology, but the molecular mechanisms driving these changes to our bodies in space, like for instance, the loss of muscular mass, are yet unknown.

A recent study ¹ in the journal Cell used a multi-omics approach to try and examine these mechanisms. The researchers employed data from NASA’s GeneLab and NASA’s Twin Study. In total they gathered information from 59 astronauts and other samples flown in space, including human cell models, mouse strains, and mouse and human tissues. As an omics study, it aimed to assess transcriptomic, proteomic, metabolomic and epigenetic changes in response to spaceflight.

When they analysed the data in all of these domains through pathway analysis they found a significant enrichment in mitochondrial processes. But they were not the only ones they found altered, also other pathways related to immunity, inflammation, cell cycle or circadian rhythm were affected. The most curious finding was that olfactory function also seemed to be affected by spaceflight.

Some of these findings in NASA’s GeneLab samples were corroborated in the NASA’s Twin Study, while urine and blood metabolic data both from the astronauts and Twin Study data revealed altered mitochondrial function and DNA damage.

Together, these findings indicate that mitochondrial stress is a constant associated with spaceflight, and that it is probably the underlying cause for the health risks associated with flying out into space. Obviously, these findings will have implications for the planning of long space missions and the following supervision of health indicators once they get back to earth.