The biological process that protects black bears’ bones during hibernation could help people with bone-related chronic illness and to protect astronauts on long space flights. Photograph: Andrew Krech/AP
by Philip Oldfield
Astronauts could protect themselves against bone wastage by harnessing a unique biological process that allows black bears to maintain their skeletons during hibernation.
A study has revealed that bears protect their bones from degrading, despite hardly moving for up to six months, by suppressing the usual constant release of calcium from the bones into the blood.
Such a lengthy period of inactivity in humans would lead to a severely weakened bone structure.
“This could be the basis for a new therapy for astronauts, or people with a bone-related chronic illness,” said Meghan McGee-Lawrence, assistant professor in cellular biology and anatomy at Georgia Regents University in Augusta, and an author of the study.
Astronauts will spend a year in space testing effects on body and mind.
Reduced movement in humans, and other mammals, can cause significant health problems. This is due to the body responding to inactivity by decreasing bone formation and increasing calcium release, leading to bone loss and increased risk of breaks and fractures.
One of the major side-effects of prolonged weightlessness is spaceflight osteopenia, a condition where reduced stress on the bones triggers bone loss. Astronauts on the Mir space station, for example, lost on average 1-2% of their bone mass each month.
The condition can be a limiting factor for the length of missions that astronauts can endure.