FOLLOWING A novel study of mice aboard a Russian spaceflight, researchers have raised a question for astronauts of tomorrow: could travelling in space be bad for your joints? They found early signs of cartilage breakdown in the mice, suggesting that the reduced biomechanical forces of spaceflight are at play on the musculo-skeletal system.
The study, published online in the journal npg Microgravity, was done by researchers of Henry Ford Hospital in the United States. While they agree that it is premature to translate the finding to humans, they also note that previous research has shown that living and working in space leads to many changes in the human body including the immune system, blood pressure and the shape of a person’s eyes.
In the new study, evidence of articular cartilage breakdown in the mice was “clear-cut”, according to lead author Jamie Fitzgerald. “We believe this degradation is due to joint unloading caused by the near lack of gravity in space. If this were to happen to humans, given enough time, it would lead to major joint problems,” Dr Fitzgerald was quoted as saying.
Researchers believe that because the biomechanical forces in space are different from those on Earth, changes to the musculo-skeletal system occur. “This muscle and bone loss are reversed when the astronauts return to Earth. What is interesting about cartilage is that it’s a tissue that repairs very poorly. This raises the important question of whether cartilage also degrades in space,” Dr Fitzgerald was quoted as saying.
The research team analysed the molecular changes in the cartilage of mice that spent 30 days in animal research enclosures aboard an unmanned Russian Bion-M1 spacecraft in 2013. This included performing tissue stains and gene expression studies on the cartilage. The results were compared to mice observed on Earth during the same period. The changes were found to be consistent with those associated with osteoarthritis. In comparison, the mice on Earth showed no discernible cartilage degradation.
The study was funded by NASA, which is keen on developing a better understanding of what happens to the human body in space. The researchers said more studies are needed, especially given that there is a potential trip to Mars in the future. —Source: Henry Ford Health Systems