Molecular changes in the livers of space travelers may provide important clues about aging, according to findings released on Jul. 7 by a team led by Michal Masternak at the University of Central Florida.
The research team identified molecular changes in the liver that occur when subjects are exposed to radiation and microgravity, conditions similar to those experienced during prolonged space missions. These changes, which resemble accelerated aging, could increase health risks for astronauts and highlight potential targets for therapies against age-related diseases on Earth.
For their study, UCF researchers and scientists from the United States created a simulated deep space environment in the laboratory. Animal models were exposed to simulated microgravity for 14 days as well as galactic cosmic radiation and solar particle events at NASA Space Radiation Laboratory. The dosage aimed to mimic what astronauts would experience during a trip to Mars. The exposure led to increased cellular senescence, inflammation, and fibrosis in the liver—conditions that can lead to declining or failing organ function if left untreated.
The team compared these results with data from astronaut blood samples collected during the NASA Twins Study and Inspiration4 mission. They observed similar genetic changes. "We've got this raw data from human studies, and they show that some of these changes are similar," Masternak said. "That tells us we're identifying useful molecular targets that one day could help protect astronauts during long-duration space missions."
Researchers also investigated possible treatments for these molecular alterations by identifying antagomirs—a group of molecules capable of altering several aging and inflammatory genetic pathways through interactions with microRNA—as promising candidates for future therapies.
"Very often when we study different aging processes, it takes time," Masternak said. "Even in humans, it's almost impossible because it would take decades. But if we see some acceleration of aging in space, then we can translate it to human studies. We can observe processes happening much faster, understand them better, and eventually use that knowledge to improve health for people here on Earth." College of Medicine students involved with this research expressed interest in further exploring how extreme environments affect human biology.
