Even short trips into space can change an astronaut's biology – a brand new series of studies offers essentially the most comprehensive insight into the health of astronauts during space flights since NASA's twin study

Only about 600 people have ever traveled into space. The overwhelming majority of astronauts For the past sixty years, the soldiers have been middle-aged men on short-term missions of lower than twenty days.

Today, we’re witnessing a brand new era of human spaceflight as more private, industrial and multinational space operators and aviators enter the market, with missions lasting from minutes, hours and days to months.

As humanity hopes to return to the moon in the approaching decade, space missions will last significantly longer and can involve many more astronauts and even space tourists. This also implies that a greater diversity of individuals will experience the acute conditions of space – more women and folks of various ethnicities, ages and health conditions.

Because people respond in another way to the unique stressors and pressures of space, space health researchers like me try to raised understand the impact of spaceflight on human health. With such information, we will work out the way to help astronauts stay healthy each in space and after they return to Earth.

As a part of the historical NASA twin studyIn 2019, my colleagues and I published groundbreaking research on how a 12 months aboard the International Space Station affects the human body.

I’m a Radiation cancer biologist within the Department of Environmental and Radiation Health Sciences at Colorado State University. I even have spent the previous few years expanding on this earlier research in a series of recent articles published in your entire Nature journal portfolio.

These papers are a part of the Manuscript package “Space Omics and Medical Atlas”Data, protocols and repositories representing the biggest collection ever assembled for aerospace medicine and space biology. Over 100 institutions from 25 countries have contributed to the coordinated release of a wide selection of space data.

The NASA twin study

NASA Twin study seized a singular research opportunity.

NASA chosen astronaut Scott Kelly for the agency's first year-long mission, during which he spent a 12 months aboard the International Space Station from 2015 to 2016. During the identical period, his an identical twin brother Mark Kelly, a former astronaut and current U.S. Senator for Arizona, remained on Earth.

My team and I examined blood samples collected before, during and after spaceflight from our twin and his genetically an identical twin on Earth. We found that Scott's telomeres – the protective caps on the ends of chromosomes which can be just like the plastic tip on a shoelace that keeps them from fraying – grew unexpectedly longer during his 12 months in space.

When Scott returned to Earth, nonetheless, his telomeres began to shorten rapidly. In the months that followed, his telomeres recovered, but were still shorter after his trip than that they had been before his flight into space.

As you age, your telomeres shorten on account of various aspects, including stress. The length of your telomeres can function a biological indicator Your risk of developing age-related diseases equivalent to dementia, heart problems and cancer.

In a separate studyMy team studied a bunch of 10 astronauts on six-month missions aboard the International Space Station. We also had a control group of age- and gender-matched participants who stayed on Earth.

We measured telomere length before, during and after spaceflight and again found that telomeres were longer during spaceflight and shortened after returning to Earth. Overall, the astronauts had many more short telomeres after spaceflight than before.

One of the opposite researchers within the twin study, Christopher Masonand me conducted one other telomere study – this time with two high-altitude mountaineers – a similarly extreme environment as on Earth.

We found that the climbers' telomeres were longer after they climbed Mount Everest and shortened again after they descended. Their twins who stayed at low altitude didn’t experience the identical changes in telomere length. These results suggest that it was not the microgravity of the space station that caused the changes in telomere length we observed within the astronauts – other causes, equivalent to increased radiation exposure, are more likely.

Civilians in space

In our latest studyWe studied the telomeres of the crew aboard SpaceX's 2021 Inspiration4 mission. This mission had the primary all-civilian crew whose ages spanned 4 a long time. All crew members' telomeres lengthened through the mission, and three of the 4 astronauts also showed telomere shortening after returning to Earth.

What's particularly interesting about these findings is that the Inspiration4 mission lasted only three days. So not only do scientists now have consistent and reproducible data on how telomeres reply to spaceflight, but we also know that it happens quickly. These results suggest that even short trips, like a weekend trip to space, are related to changes in telomere length.

The health implications of such changes in telomere length should not yet fully understood by scientists. We have to do more research to know how each long and short telomeres affect an astronaut's long-term health.

Telomere RNA

In one other articlewe showed that the Inspiration4 crew – in addition to Scott Kelly and the high-altitude climbers – had elevated levels of telomeric RNA, called TERRA.

Telomeres consist of various repeating DNA sequences. These are transcribed into TERRA, which contributes to the structure of the telomeres and helps them perform their function.

Together with laboratory studies, these results show that telomeres are damaged during space travel. Although there continues to be much we have no idea, we do know that telomeres are particularly sensitive to oxidative stressThe chronic oxidative damage that astronauts suffer from 24/7 exposure to space radiation likely contributes to the telomere responses we observe.

We also wrote a Review article with a more futuristic perspective how a greater understanding of telomeres and aging could help humans not only survive long space journeys, but in addition thrive and even colonize other planets. This would require humans to breed in space and future generations to grow up in space. We don't yet know if that is even possible.

Plant telomeres in space

My colleagues and I even have also contributed other work to the Space Omics and Medical Atlas package, including an article published in Nature CommunicationsThe study team led by Texas A&M biologist Dorothy Shippen and biologist at Ohio University Sarah Wyattfound that plants in space didn’t have longer telomeres during their time aboard the International Space Station, unlike humans.

However, the plants increased their Production of telomerasethe enzyme that helps maintain telomere length.

As anyone who has seen “The Martian“As we all know, plants will play an essential role in the long-term survival of humans in space. This finding suggests that plants may be naturally better equipped to withstand the stresses of space than humans.”