They're growing bones on the International Space Station. There's a reason for that, of course: the scientists hope to gain new insights into skeletal weakening and atrophy in the hope that findings will lead to treatments for bone loss, which happens not only to those in long-term zero-gravity environments, but also to older folks here on Earth.
A group of 40 rodents will call the International Space Station home for two months, during which scientists will test a bone-growth molecule on them in a microgravity environment. Microgravity, which happens when an object (or rodent) is in free fall, lets scientists produce changes in bone and organ systems that can't be replicated on Earth.
It may come as a surprise to find that we've been doing this sort of thing for years; my wife worked on the STS-80 Space Shuttle project, looking into changes in calcium and blood pressure effects of microgravity. Calcium balance, as it happens, turns out to be critical to maintenance: your bones are constantly absorbing and excreting the stuff. In certain circumstances, such as microgravity or aging, the balance is thrown off; they start excreting faster than they absorb, which is why an 80 year-old suffers hip fractures after a fall that would leave a kid unaffected. On Earth, we call the phenomenon osteoporosis. And this leads us to the next step:
The same thing happens to much younger people in space. So this test is designed to determine whether a molecule that directs stem cells to produce more bone works as well in microgravity as it does in test animals here.
The study hopes to gain insight into better ways to prevent bone loss for astronauts on long flights and for patients back on Earth.
The research, which will begin on the ground sometime soon, is funded by grants from the Center for the Advancement of Science in Space and National Institutes of Health.
My wife's study was funded by NASA-Ames Reseach Center and NIH, and the results laid the groundwork for this study, among others.