microgravity’s effect on bone density tagged posts

Comparing volume and activity of the cells that break down bone density in the upper and lower jaw bones of Medaka fish after 56 days spent aboard the International Space Station with those on the ground. Credit: Chatani et al, Sci. Rep. 5, 14172 (2015)

During spaceflight, astronauts lose bone mineral density, but it is not clear exactly what causes this loss. They reared small freshwater fish aboard the International Space Station for 56 days and examined the animals’ jawbones and teeth for any effects from microgravity. Previous studies suggest that microgravity activates osteoclasts, cells that control the breakdown of bone tissue, and the Medaka fish investigation examined the relationship between this increased osteoclast activity and reduced bone mineral density.

Investigators found ...