Study of muscle loss in space may benefit patients on Earth

Scientists onboard the International Space Station (ISS) are assessing the ability of a novel compound to prevent skeletal muscle wasting and weakness in mice exposed to long-duration spaceflight.
The findings will advance our understanding of the risks that long-term space exploration poses to astronauts, and can be applied towards the development of counter-measures to protect health of astronauts, researchers said.
Exercise and eating right is a common prescription for maintaining muscle and building bone, but more advanced solutions are needed to address serious diseases that lead to loss of muscle function in the general population.
The ISS provides researchers a unique opportunity to study muscle loss and to investigate means for muscle preservation.

Rodent Research-3 is a study launched aboard the eighth SpaceX resupply mission to the space station this month.
When we unload, or remove the force of our body weight from the muscles that normally work against gravity to support us, those muscles rapidly atrophy, or waste away and weaken.

That is exactly what happens in microgravity unless counter-measures are applied. The astronauts on the space station, for example, follow rigorous exercise programmes that apply forces to their musculo-skeletal systems and help them stay strong throughout their missions.
Mice exposed to spaceflight have proved to be valuable research models to understand, target and treat causes of human muscle atrophy.

"This includes modelling serious diseases that involve muscle wasting such as muscular dystrophy, amyotrophic lateral sclerosis, cancer cachexia and even ageing-related musculoskeletal frailty," said Rosamund Smith, the principal investigator for the Rodent Research-3 mission.
"The ability to expose all muscles of an organism to conditions that induce muscle atrophy is not easily achieved on Earth," said Smith.
Loss of muscle function, rather than just a decrease in muscle size, is the critical aspect that leads to problems with physical performance in patients suffering from muscle-wasting conditions.
"The Rodent Research-3 study is unique not only in the experimental compound that will be tested, but also because, for the first time, muscle function of the mice will be assessed during spaceflight," said Janet Beegle, Rodent Research-3 project manager at NASA's Ames Research Centre in US.

Although the primary research focus of Rodent Research-3 is skeletal muscle, the researchers are studying other organ systems, such as bone, both at the tissue and molecular levels.
Their goal is to characterise tissue responses to spaceflight and observe how these changes vary with the length of time spent in microgravity.