In more bad news for astronauts, a new study by the Georgetown Lombardi Comprehensive Cancer Center suggests that space travel can cause a cell's mitochondria to malfunction due to changes in gravity and radiation.
When the idea of space travel was first taken seriously, solving the problem of living in space seemed pretty straightforward. Aside from the lack of gravity, it wouldn't be much more difficult than staying alive and comfortable in a submarine or a high-altitude aircraft. It was simply a matter of making sure that there was enough air, maintaining the right temperature, and controlling the humidity.
Unfortunately, in the almost six decades since the first human was launched into space, scientists have learned a great deal about how the human body reacts to living in the weightless, relatively high-radiation environment of space, and the answers have not been good. Space can have all manner of effects, including damaged vision, bone loss, muscle atrophy, and compromised immune systems.
The Georgetown Lombardi study now adds the depressing prospect that weightlessness and cosmic radiation, along with other factors, can also affect the body on a sub-cellular level by damaging the mitochondria – the powerhouse of the cell that turns sugar into energy.
In order to better understand these effects, the Georgetown Lombardi team looked at the tissue of mice that had flown in space, as well as drawing on NASA's collection of flown bio-specimens and astronaut data, including the space agency's Twin Study of astronauts Mark and Scott Kelly.
"My group’s research efforts centered around muscle tissue from mice that were sent into space and were compared with analyses by other scientists who studied different mouse tissue," says Evagelia C. Laiakis, PhD, an associate professor of oncology at Georgetown. "Although we each studied different tissue, we all came to the same conclusion: that mitochondrial function was adversely impacted by space travel."
The findings also showed that isolated cells were affected more than whole organs, and that the liver was affected more than other organs.
While this effect may be a matter of concern for astronauts on long voyages into deep-space, the bright side is that it can also help in developing better radiotherapy for cancer patients back on Earth.
“From this and other planned ventures to the moon, and eventually Mars, we hope to learn much more about the effects that spaceflight can have on metabolism, and how to potentially mitigate adverse effects for future space travelers,” says Laiakis.
The study was published in Cell.
