Astronauts floating weightlessly in the International Space Station may appear carefree, but years of research have shown that microgravity causes changes to the human body. Spaceflight also means exposure to more radiation. Together, microgravity and radiation exposure add up to pose serious health risks. But research is not only making space safer for astronauts, it's helping to improve health care for the Earth-bound as well.
One of the effects of space radiation is damage to DNA, or deoxyribonucleic acid, the genetic material in nearly every cell of our bodies. When damaged DNA repairs itself, errors can occur that increase the risk of developing cancer. A new study, MicroRNA Expression Profiles in Cultured Human Fibroblast in Space -- Micro-7 for short -- will examine the effect of gravity on DNA damage and repair. Because there is no controlled radiation source aboard the space station, the cells will be treated with bleomycin, a chemotherapy drug, to induce DNA damage.
"When a cell in the human body is exposed to radiation, DNA will be broken and repaired, which is considered the initiation stage of tumor development," explains principal investigator Honglu Wu, Ph.D., at NASA's Johnson Space Center in Houston. "Cells damaged from radiation exposure in space also experience microgravity, which we know changes gene expressions even without radiation exposure." That equals the space double-whammy for the human body.To read more, click here.