Mitigating Microgravity Weakness In Space

It has long been known that prolonged space flight can lead to a weakened immune system, largely due to the biological effects of microgravity. Testing these weakening effects on fruit flies, researcher have outlined several ways to stave off space-borne weakness.

"What we don't realize in our everyday lives is that every biological, chemical and physical process that takes place in our terrestrial environment of Earth happens under the influence of gravitational forces," Camille Alleyne, a NASA space program scientist explained in a statement. "Conducting scientific investigations on the space station, such as that on the fruit flies, allows us to remove that gravitational element from the equation, and advances our knowledge about these same processes that lead to amazing breakthroughs and discoveries."

In this most recent study, published in the journal PLOS One, researchers at the Johnson Space Center and the University of California (UC) analyzed how microorganisms may alter the immune systems of fruit flies when affected by various levels of gravity.

Researchers determined long ago that fruit flies boast an immune system, remarkably similar to the human system, despite how different the two species are.

In 2006, a small sample of fruit flies were shuttled to the International Space Station during Discovery's STS-121 mission. The flies developed and matured over the 12-day mission, with their numbers swelling.

Simultaneously, an identical group of the flies were exposed to hypergravity - gravitational conditions more intense than Earth's - in a centrifuge at UC Davis.

When both groups were back on earth, researcher analyzed their immune systems - especially measuring how the flies responded to various infections. Interestingly, they had mixed results.

"What we found is that in one kind of infection in flies that were raised in space, they did fine, and in another kind of infection, they really didn't respond at all," said lead investigator Deborah Kimbrell.

According to Kimbrell's observations, the hypergravity group proved resistant to fungal infections, while the microgravity group proved exceedingly vulnerable. Meanwhile, when exposed to E. coli bacteria, both groups proved increasingly resistant to infection, compared with a standard rate of infection among Earth-gravity flies.

Kimbrell says that this could imply some surprising things, where even a short term exposure to increased gravity - like a ride on a roller coaster - could potentially have positive effects on the human immune system.

Of course, far more research will be need to be conducted in various gravitational settings before this theory can be confirmed.