A new study demonstrates that sarcopenia-related muscle decline associated with aging can be modeled within a relatively short period in space, paving the way to study potential treatments quicker and more effectively.
To understand the changes of muscle in microgravity, researchers at the University of Florida (US) engineered skeletal muscle microtissues from donor biopsies and launched them to the International Space Station aboard SpaceX CRS-25.
Their findings may inform therapies for sarcopenia, which is common with aging and affects up to 50% of people aged 80 and older, according to estimates.
“Using electrical pulses to trigger real-time muscle contractions in space, we can simulate exercise and observe how it helps protect against rapid muscle weakening in microgravity,” explains Siobhan Malany, one of the lead researchers.
“This technology advancement offers insight into how we might preserve muscle health during long-duration space missions and ultimately, how to combat age-related muscle loss here on Earth.”
Spaceflight-induced muscle weakness offers a rapid model for studying age-related sarcopenia, which typically develops over decades on Earth.Apart from lifestyle changes, there is no current clinical treatment for sarcopenia. It can lead to disability and injuries from falls and is associated with a lower quality of life and an increased mortality.
Muscles in space
Space flight comes with the absence of gravity and limited strain on muscles, which causes weakness, a prominent feature of sarcopenia, within a short period of time. This offers a “time lapse view” on age-related atrophy-associated changes in the muscle, highlight the researchers.
“This relatively short window of time in space provides a microgravity model for muscular aging and opens opportunities for studying sarcopenia, which normally takes decades to develop in patients on Earth,” notes the research team.
The microtissues were taken from young, active donors, and aged, sedentary donors and cultured in an automated mini lab. Besides regular feeding and monitoring of cultures, the lab also performed electrical stimulation to simulate exercise.
On Earth, the contraction strength of microtissues from young, active individuals was almost twice as much as the strength of tissues from older, sedentary individuals. After only two weeks in space, muscle strength tended to decline in the young tissues and was now more comparable to the strength of old tissues.
A similar trend was observed in muscle protein content, which was higher in young microtissues on Earth compared to old microtissues but decreased in microgravity to levels measured in old tissues. Further, space flight changed gene expression — particularly in the younger microtissues — and disturbed cellular processes related to normal muscle function.
Interestingly, the scientists found that electrical stimulation could mitigate these changes in gene expression “to some extent.”
Their findings were published in Stem Cell Reports.
In other aging-focused space research, David Beckham’s IM8 supplement brand, co-founded with Prenetics, sent specially designed 3D organoids — miniature, simplified versions of human tissues — into space to study accelerated aging. The researchers also leveraged microgravity’s unique environment that speeds up this process.