Our slim body of knowledge of the universe is vastly overshadowed by what we do not know – whether there is sentient life on other planets, whether there are other planets that can sustain human life, even how long-term space travel physically affects human beings.
Boise State professors Gunes Uzer and Julia Oxford have been awarded a one-year, $37,000 grant from NASA to research that last question. Gunes, an assistant professor of mechanical and biomedical engineering, and biology professor Oxford are studying the impacts of bone loss in space – in other words, how living in a gravity-free environment affects astronaut health in terms of incidents of osteoporosis and other musculoskeletal diseases.
Bone fracture risk due to weightlessness is a significant challenge for future space missions. Here on earth, individuals who cannot bear weight on a limb or limbs due to injury, aging or disease, risk bone deterioration that can impact their quality of life. These risks are paralleled on space missions by a lack of gravity. To prevent microgravity associated bone loss, astronauts exercise rigorously two hours per day, on average. However, it is unlikely that these long exercise regimens will able to keep up with continual bone loss during longer space missions planned in near future, which means researchers need new strategies to slow bone loss and more fully harness exercise’s potential.
Uzer and Oxford aim to do just that with their project, “Role Cellular Connectivity in Maintaining Osteogenesis under Simulated Microgravity in Response to Mechanical Challenges.” The researchers have shown that being exposed to periods of low-intensity mechanical signals (LMMS) helps promote bone density and growth. Essentially, the researchers created gentle platforms for astronauts to stand on that buzz between 30 to 90Hz frequency and 0.1-1g magnitude (1g is what glues people to earth).
“Think like you are standing on a giant iPhone and someone calls you,” Uzer explained. “Ultimately, this signal is an approximation of the forces generated by the muscular contractions during a nice walk along the green belt … your cells know and recognize these signals.”
Uzer and Oxford believe that LMMS promotes bone density and growth. Not only that, but these mechanical signals could strengthen intracellular proteins called LINC (Linker of Nucleoskeleton and Cytoskeleton), which in some sense wakes the cells up and make them more aware of their surroundings, including exercise.