Russian scientists have studied the blood of 18 cosmonauts to see the effects of space flight on the human body. Their findings show that our bodies fight weightlessness the way they fight infections.
Zero gravity does strange things to the human body.
Scientists have been studying how space travel affects the human body since the Space Race first began. Now that our sights are set even more on exploring space, it's imperative to gain more information on how human bodies would react to the conditions in outer space. At present, we don't fully understand the effects of leaving Earth yet, though we've been doing it for decades. Thus, it's important to find out what our intrepid men and women will face when they're in the vacuum of space.
This latest study shows that the body undergoes significant changes when in space. Luckily, these changes, which take place at the molecular level, are geared toward helping the body adapt to new conditions.
Cosmonauts in the study gave their blood before they left Earth and after their return.
What we know about space flight now is that it affects the respiratory system, heart biorhythms, metabolism, muscle tone, thermoregulation, and other physiological features of the body. What we don't know is what drives these changes at the molecular level.
Researchers drew blood from 18 cosmonauts who have gone on long missions at the International Space Station (ISS) and analyzed the concentration of 125 proteins in the cosmonauts' blood plasma. Blood was drawn from the cosmonauts 30 days before they took off for their mission, once right after they came back to Earth, and another time seven days after landing. The researchers designed this timing so they'll be able to see the changes in the protein concentration in the blood and to see how quickly the concentration returned to normal.
An instrument called mass spectrometer made it possible for the researchers to pick out a molecule and perform a quantitative analysis of a mixture of substances. Using the spectrometer, the researchers were able to discover that the concentration of some proteins remained unchanged, but the concentration of other proteins did. Some proteins recovered their pre-flight concentration levels quickly after the cosmonauts returned to Earth, but others recovered slowly. In all, 19 of the 125 proteins changed in space flight.
Are we made to explore space?
These results show that the body reacts to weightlessness in a way similar to the way it reacts to an infection. Basically, zero gravity confuses the body, and the body thus tries to turn on all of its defenses.
“Plasma proteins whose concentrations changed during flight included pathways related to oxidative stress, cytoskeleton, cell proliferation, glucose and lipid metabolism, cell damage and repair response, apoptosis, calcium/collagene metabolism, transport of lipoproteins, cellular functions, protein degradation, signal transduction and cell energy metabolism,” the researchers write in their paper. This shows that the body adapts to space flight by enacting major changes in the major cells, tissues, and organs.
The results of the study suggest that the human body does not have mechanisms that allow it to adapt quickly to the major changes caused by space flight. In essence, we're actually not made for space flight—but we're unlikely to let that stop us.
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