The Japan Aerospace Exploration Agency (JAXA) conducted the study with Tohoku University and sent the 12 mice to the International Space Station (ISS). The experiment aimed to test the effects of the protein Nrf2, which acts as a regulator of adaptive responses against various environmental stresses. Nrf2 induction is known to prevent various diseases, including cancer and diabetic complications.
Half of the mice sent to space were genetically engineered to not have Nrf2, while the remaining six were unmodified and still had Nrf2. They were transported by the SpaceX Falcon rocket and spent 31 days in space.
Previous research has shown that spending time in space can lead to problems such as bone density loss and immune dysfunction in both humans and rodents. This is due to a number of factors including microgravity and exposure to radiation in space. These changes are likened to a sped-up version of the aging people experience on Earth, making spaceflight an opportunity for scientists to study the process.
Of the two groups, the mice without Nrf2 experienced changes in blood components similar to those humans go through when aging. Meanwhile, the unmodified mice showed little changes. At the time of the launch, all the mice were healthy and gaining weight. Once in space, however, the mice without Nrf2 stopped putting on weight even though the intake of food and water across both groups of mice were the same.
Scientists believe that Nrf2 could help mitigate some of the stresses associated with space travel and, possibly, aging.
“The results highlight the significance of the role Nrf2 plays in cushioning the impact of space-derived stress,” Masayuki Yamamoto, medical biochemistry professor at Tohoku University, told Kyodo News.
Apart from benefitting astronauts who experience physical deteriorations in space, this discovery also means that Nrf2 could be a key agent in decelerating aging. Scientists hope it could pave the way for new drugs that could treat conditions linked with old age like Alzheimer’s, dementia, and diabetes.