DENVER — A Colorado State University professor is detailing new findings about the impacts of space travel on human health.
Professor Susan Bailey, along with professors from more than 12 universities, released findings from the famous 'twin astronauts study,' with brothers Mark and Scott Kelly. Scott Kelly spent more than a year in space while twin-brother Mark Kelly stayed on earth. The experiment, and resulting studies, have provided the deepest insight to date about the health impacts of human space travel.
Newly-released data show that space travel have an impact on the body's cell, specifically the makeup of chromosomes called telomeres. A telomere is essentially a protective cap that sits over the ends of a chromosome. As humans age, the protective cap is shortened. The shortening is a consequence of cell-replication.
"Telomeres shorten with cell division, so they become a very important marker of aging," explained Professor Susan Bailey. "So a very major theory of aging is related to telomere shortening."
A contributing factor in the shortening of telomeres is stress and exposure to radiation. Therefore, scientists hypothesized that astronauts in space would reduce the length of their telomeres. However, they found the exact opposite.
"We looked at blood, we looked at urine, and we saw the very same thing," said Bailey. "That the telomeres overall were longer during spaceflight."
Another interesting phenomenon was that once the astronauts returned to earth, the length of their telomeres shrank, sometimes shorter than they were before. Telomere length has implications for human health. Longer telomeres is correlated to an increase in cancer probability whereas shorter telomere length has implications for heart disease.
"Long telomeres are not the fountain of youth. And certainly, I think in during spaceflight, it's even more of a concern, because you've got mutations going on at the same time," said Bailey. "We have to realize it and then figure out why it's happening and then hopefully be able to do something about it."