Writing in Nature, the researchers also suggest that the Human Cell Atlas project, which maps all cell types in the body, could be replicated in space to provide an open, global resource for science research.
“There is a motive for scientists across the world to study how the human body responds to spaceflight and to develop countermeasures that improve the health and safety of crewed interplanetary missions,” the researchers wrote. “We propose the development of a human cell atlas under spaceflight environmental conditions that could assist as an openly available, global resource for foundational space life science research.”
The study of -omics
The time that astronauts spend in space has increased, although only eleven people have spent more than 300 consecutive days in orbit. If humans make it to Mars, they will spend longer periods in radiation-heavy environments and there is limited understanding about how that will impact the body.
Additionally, the chance that a medical emergency will occur is about one event every 2.4 years for a crew of seven, the researchers noted.
“Multiyear planetary missions would prevent resupply and medical evacuation options and hence would require fully autonomous telehealth and triage protocols,” they wrote.
Beyond safety measures, the researchers looked to previous space studies to gauge the potential of a biomedical research platform that could lead to the creation of precision spaceflight health care. In the NASA Twins Study, scientists uncovered more than 8,600 genes that were expressed differently between an astronaut and their identical twin who remained on Earth.
The study integrated transcriptomics, epigenomics, metabolomics and metagenomics platforms, marking ‘omics’ as a potential biomedical research platform.
Micronutrients
The researchers suggest that prolonged radiation exposure may “interact with genetic polymorphisms that alter micronutrient metabolism, predisposing to disease in space.”
Some preliminary evidence indicates that space changes iron metabolism in astronauts. Concurrently, urinary magnesium levels may decrease during space travel, as a majority of astronauts have levels below minimum clinical guidelines when they return home.
When it comes to vitamin D, certain genes are associated with a better response to supplementation, although poor vitamin D status of astronauts across the board during space missions can negatively influence the immune system but this could “potentially be mitigated through precision omics profiles,” the researchers wrote.
Macronutrients
Again, genes play a role in nutrient consumption needs and variants are associated with body composition, fat distribution and obesity risk.
The researchers wrote that “Initial studies have suggested that endocrine changes linked to spaceflight modify metabolism and strengthen its association with alterations in astronaut body composition and nutritional intake needs.”
They added that prolonged space travel seems to affect metabolic stress, changing gut flora, feeding behavior, vitamin insufficiency and electrolyte imbalance and that maintaining energy balance during missions will be essential to maintaining body fat muscle homeostasis.
However, these changes in the body impact each astronaut differently, underscoring the need for both precision health and a large-scale research platform.
“In the coming years, humans may venture into space for unprecedented durations and distances outside of the Earth’s radioprotective magnetosphere,” the researchers wrote. “Precision healthcare is becoming more commonplace for populations on Earth, where international consortiums are using high-resolution omics to construct the Human Cell Atlas…The cell space atlas could serve as an open access, global reference for basic space life science research.”
Source: Nature
2024, 15, 4952. doi: 10.1038/s41467-024-47237-0
"Astronaut omics and the impact of space on the human body at scale"
Authors: Lindsay A. Rutter et al.
