By Drew Joseph
One year from now, in a lab far, far away, a group of fruit flies could unknowingly be helping to make long-term space travel safer.
An experiment led by local researchers will use fruit flies to study how the lack of gravity and changes in radiation in space affect the cardiovascular system of humans. It was one of eight projects recently selected by Space Florida, the state’s aerospace authority, for a 30-day trip to the International Space Station set for December 2013.
Time spent in little gravity can atrophy muscle and bone, and astronauts have returned to Earth with lower heart mass and higher incidents of irregular heart rhythms, said Dr. Peter Lee, a cardiothoracic surgeon at Stanford who is helping to run the fruit fly study.
But experts do not understand how significant the cardiovascular problems might be or the mechanisms behind the changes. That’s where the fruit flies and their itty-bitty hearts come in.
Fruit flies and humans contain many similar genes, meaning scientists can infer how decreased gravity affects people by seeing what happens to the flies, which are also known as drosophila.
“We can learn so much translationally from a simple model system,” said Sharmila Bhattacharya, the principal investigator of the Biomodel Performance Laboratory at the NASA Ames Research Center. “It’s a simple organism that pretty much mirrors a lot of the important functions of humans.”
Impacts of space
One goal is to understand how the changes in gravity and radiation levels between Earth and space might affect genes related to heart function — perhaps making some more active or slowing others down. Researchers also will examine if the flies’ hearts lose any contractile strength and if they shrink or have other structural changes.
And once researchers figure out how the cardiovascular system responds to space travel, they might be able to mitigate effects for astronauts sent on missions deeper into space.
Lee said the team is still determining how many flies will go to the space station in the small containers that will house the flying guinea pigs.
“Space is sexy, I guess, in a lot of ways,” Lee said of people’s fascination with the project. “But there are a lot of real challenges and questions that need to be addressed to make long-duration space flight possible.”
Bhattacharya has worked with flies in space before, including on one study that showed that flies returned with a weakened immune system — another effect that had been seen in astronauts. She and Lee are partnering with scientists from the Sanford-Burnham Medical Research Institute in La Jolla for the project.
Another project selected by Space Florida was designed by UC Davis researchers. It compares the microbial environments of buildings on Earth to that of the space station.
One point of the project is to engage the public in science, specifically in microbiology. With help from the group Science Cheerleader, organizers will hold events in places like stadiums and conference halls where attendees will collect samples of microbes. Some of those samples will be shipped to the space station to see how the microbes grow there.
It’s part of an effort to get people to think about the microbes that live with us and how different types of buildings may have different communities of microbes, researchers said.
“The science is interesting, but this is more about teaching people about microbial ecology in a built environment,” said Jonathan Eisen, a UCD microbiologist who is helping to organize the project.
Bringing microbes back
Astronauts also will collect microbes from the space station for Eisen to analyze back on Earth. The station should have an interesting array of microbes because the only ones there had to be on the station initially or come from the astronauts who traveled there, Eisen said.
The projects will hitch a ride to the space station on a SpaceX Falcon 9 rocket leaving from Cape Canaveral Air Force Station. And no, the researchers will not be tagging along.
“I would go,” Eisen said, “but that seems unlikely.”
— Reach Drew Joseph at [email protected]