loss of bone material due to the onset of osteoporosis. Since the microgravity environment
is known to stimulate the loss of bone material in adults in a very short period of time, the
spaceflight microgravity environment is the ideal location to conduct experiments aimed at
understanding bone loss. By using the ADF, specimens can be incubated in the exact same
environment with the only difference being 1 g versus microgravity. This experimental
condition is not available on Earth and is critical to specifically isolating the cause of bone
material loss. It is anticipated that the data from this ADF study can provide scientists with key
information to identify the specific biological processes that contribute to bone loss and the
mechanism of this disease process. Overall, the identification of the specific biological
processes can provide scientists and pharmaceutical companies candidate targets for the
development of therapeutic agents.
SPACE BENEFITS
The ADF is the first step to creating new technologies
that can support critical biological research in direct
support of human space travel. The subsystems used
to support the biological specimens can be applied to
technologies directed to supporting other animals or
the crew.It is a known fact that crew members lose bone
material soon after they enter the weightless
environment of space. The loss of bone material
poses a significant health risk because the crew
members’ bones weaken and become more
susceptible to breakage. Also, since they are adults,
their body's ability to regenerate the lost bone
material once they return to Earth is very limited.
Currently, no therapies exist that can stimulate the
production of new bone material. The spaceflight
microgravity environment is ideal for studying bone
formation and material loss because its effects on the
skeleton are rapid and occur within days of entry into
space. This ADF-Skeletal experiment is designed to
investigate the biological processes that are key to
stimulating new bone formation. By using the ADF,
this experiment can control the embryogenesis
environment so that components affected by the
spaceflight environment, especially microgravity, can
be identified. By comparing the data to the simulated
1 g in flight controls and ground controls, the ADF
experiment can identify specific changes to bone
formation that are due to the microgravity environment, which in turn, points out the specific
biological systems (molecular, cellular, and systemic) that are sensitive to changes in gravity.
Electron micrographs of quail limb bones that
formed under the influence of microgravity
show decreased mineralization compared to
bones formed in normal gravity. The letters
"B" and "C" indicate bone and cartilage sides
of the sample, respectively, with the arrows
marking the junction between bone and
cartilage cells. The asterisks indicate where
mineralization begins. The bone that
developed during spaceflight (top) shows
less mineral compared to the control sample
(bottom); the control sample clearly shows
mineral deposits (dark spots) that are absent
in the flight sample. NASA’s Johnson Space
Center image.