On Earth, our our bodies create and destroy 2 million pink blood cells each second. In a brand new research revealed in the present day within the journal Nature Medicine, a staff of scientists from the Ottawa Hospital Research Institute and the University of Ottawa discovered that astronauts have been destroying 54% extra pink blood cells throughout their 6-month missions onboard the International Space Station, or 3 million each second.
Trudel et al. counsel that the destruction of pink blood cells, termed hemolysis, is a major impact of microgravity in house flight and help the speculation that the anemia related to house flight is a hemolytic situation that ought to be thought-about within the screening and monitoring of each astronauts and house vacationers. Image credit score: NASA.
“Space anemia has consistently been reported when astronauts returned to Earth since the first space missions, but we didn’t know why,” mentioned Professor Guy Trudel, a rehabilitation doctor and researcher on the Ottawa Hospital Research Institute and the University of Ottawa.
“Our study shows that upon arriving in space, more red blood cells are destroyed, and this continues for the entire duration of the astronaut’s mission.”
Before the brand new research, house anemia was regarded as a fast adaptation to fluids shifting into the astronaut’s higher physique once they first arrived in house.
Instead, the authors discovered that the pink blood cell destruction was a major impact of being in house, not simply brought on by fluid shifts.
They demonstrated this by straight measuring pink blood cell destruction in 14 astronauts throughout their six-month house missions.
“Thankfully, having fewer red blood cells in space isn’t a problem when your body is weightless,” Professor Trudel mentioned.
“But when landing on Earth and potentially on other planets or moons, anemia affecting your energy, endurance, and strength can threaten mission objectives.”
“The effects of anemia are only felt once you land, and must deal with gravity again.”
In the research, 5 out of 13 astronauts have been clinically anemic once they landed — one of many 14 astronauts didn’t have blood drawn on touchdown.
The researchers noticed that space-related anemia was reversible, with pink blood cells ranges progressively returning to regular three to 4 months after returning to Earth.
Interestingly, they repeated the identical measurements one yr after astronauts returned to Earth, and located that pink blood cell destruction was nonetheless 30% above preflight ranges.
These outcomes counsel that structural modifications could have occurred to the astronaut whereas they have been in house that modified pink blood cell management for as much as a yr after long-duration house missions.
The discovery has a number of implications:
(i) it helps screening astronauts or house vacationers for present blood or well being circumstances which are affected by anemia;
(ii) the longer the house mission, the more serious the anemia, which may influence lengthy missions to the Moon and Mars;
(iii) elevated pink blood cell manufacturing would require an tailored weight-reduction plan for astronauts;
(iv) it’s unclear how lengthy the physique can keep this increased price of destruction and manufacturing of pink blood cells.
According to the scientists, their findings is also utilized to life on Earth.
“If we can find out exactly what’s causing this anemia, then there is a potential to treat it or prevent it, both for astronauts and for patients here on Earth,” Professor Trudel mentioned.
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G. Trudel et al. Hemolysis contributes to anemia throughout long-duration house flight. Nat Med, revealed on-line January 14, 2022; doi: 10.1038/s41591-021-01637-7