Space may do more than weaken muscles and bones. New findings suggest that the combined effect of cosmic radiation and microgravity can trigger biological changes that resemble aging inside the body.
The liver emerged as the clearest focus of concern in the study reported by mediaindonesia.com from Earth.com and published in the journal GeroScience. Researchers found that changes could appear quickly, even after very short exposure, raising new questions about the health risks of long-duration spaceflight.
Why the liver matters most
The team led by Professor Michal Masternak of the University of Central Florida focused on the liver because it plays a central role in metabolism. It helps regulate energy, store nutrients, and neutralize toxins.
Masternak said the organ changed faster than expected. “We focused our study on the liver because this organ is one of the main metabolic centers in the body. What we found is that just 24 hours after exposure to radiation, there were many genetic changes in the liver that were very similar to the processes that happen when a person ages,” he said.
He added that longer exposure could lead to more severe damage. That makes the liver an important indicator for understanding the health risks astronauts may face on extended missions.
A Mars mission simulation showed serious shifts
To test the effects of a long space journey, the researchers built a laboratory simulation of space conditions. Animal models were kept for 14 days in artificial microgravity and exposed to galactic cosmic radiation as well as radiation from solar particle events.
The setup took place at NASA Space Radiation Laboratory and was designed to resemble the dose astronauts are expected to receive on a mission to Mars. The result showed an increase in cellular senescence, the condition in which cells age and stop functioning normally.
Researchers also detected more inflammation and fibrosis in the liver. Fibrosis is the formation of scar tissue that can interfere with organ function and, if it continues, may progress to declining function or organ failure.
| Research Aspect | Detail | Observed Impact |
|---|---|---|
| Organ studied | Liver | Genetic changes similar to aging |
| Simulation duration | 14 days | Microgravity and radiation exposure |
| Type of exposure | Galactic cosmic radiation and solar particles | Increased cellular senescence, inflammation, and fibrosis |
| Simulation site | NASA Space Radiation Laboratory | Modeled after a Mars mission |
Human data points in the same direction
To see whether the findings were relevant to people, the team compared the results with blood samples from NASA Twins Study and astronauts from the Inspiration4 mission. The comparison showed a similar pattern of genetic changes.
Masternak said the result offers an important clue to molecular targets that could someday help protect astronauts on long missions. He also noted that accelerated biological change in space could help scientists study aging in a much shorter time frame.
A possible path for future protection
The study also points to a possible protective route through antagomirs. These molecules work by influencing microRNA, which regulates gene activity inside cells.
Through that mechanism, antagomirs may help reduce the effects of cellular aging and inflammation caused by radiation exposure that mimics space conditions. The idea is still at an early stage, but it could become a basis for therapies for astronauts and for age-related conditions in people on Earth.
Masternak noted that human aging normally takes a very long time to observe. That is why accelerated biological change in space may serve as a scientific shortcut for understanding the aging process more quickly and in greater depth.
Space, in that sense, is becoming more than a place for exploration. It is also emerging as a natural laboratory for studying how the body ages and how that knowledge may someday help protect human health on Earth.
