Research provides new insights on health effects of long-duration space flight
https://web.archive.org/web/20201125160029if_/https://phys.org/news/2020-11-insights-health-effects-long-duration-space.html

The historic NASA Twins Study investigated identical twin astronauts Scott and Mark Kelly and provided new information on the health effects of spending time in space.

Colorado State University Professor Susan Bailey was one of more than 80 scientists across 12 universities who conducted research on the textbook experiment; Mark remained on Earth while Scott orbited high above for nearly one year. The massive effort was coordinated by NASA's Human Research Program.

Bailey has continued her NASA research and now joins more than 200 investigators from dozens of academic, government, aerospace and industry groups to publish a package of 30 scientific papers in five Cell Press journals on Nov. 25.

Jared Luxton, who recently received his doctoral degree in cell and molecular biology at CSU, is the first author of two of the studies. He is now a data scientist with the United States Department of Agriculture in Fort Collins.

The research—including an over-arching paper that covers what the investigators have learned about the fundamental features of space flight—represents the largest set of space biology and astronaut health effects data ever produced.

For Bailey, it is also a milestone marking many years of working with NASA, which included her lead role on basic radiation studies and the honor of being selected as an investigator for the Twins Study and concurrent research projects involving astronauts. During this time, several graduate students in her lab earned doctoral degrees under her mentorship.

"We now have a foundation to build on—things we know to look for in future astronauts, including telomere length changes and DNA damage responses," Bailey said. "Going forward, our goal is to get a better idea of underlying mechanisms, of what's going on during long-duration space flight in the human body and how it varies between people. Not everybody responds the same way. That was one of the good things about having the larger cohort of astronauts in these studies."

Studying the ends of chromosomes, with implications for aging

Bailey is an expert on telomeres and radiation-induced DNA damage, areas of research that were of keen interest around the world when the Twins Study was published. In that study, she and her team found that Scott's telomeres in his white blood cells got longer while in space, and subsequently returned to near normal length after he was back on Earth.

Telomeres are protective "caps" on the ends of chromosomes that shorten as a person ages. Large changes in telomere length could mean a person is at risk for accelerated aging or the diseases that come along with getting older, cardiovascular disease and cancer for example.

In the latest research, Bailey, Luxton, Senior Research Associate Lynn Taylor and team studied a group of 10 unrelated astronauts, including CSU alum Dr. Kjell Lindgren, comparing the results with findings from the Kelly twins. The researchers did not have access to in-flight blood and other samples for all of the crewmembers, but Bailey said they did have blood samples before and after space flight for everyone.

The investigations involved astronauts who spent approximately six months on the International Space Station in low-Earth orbit, which is protected from some space radiation. Despite the protection, scientists found evidence of DNA damage that could be warning signs of potential health effects.

Among the new findings, the research team found that chronic oxidative stress during spaceflight contributed to the telomere elongation they observed. They also found that astronauts in general had shorter telomeres after spaceflight than they did before. The team also observed individual differences in responses.

To gain more insight on these findings, Bailey's team also studied twin mountain climbers who scaled Mt. Everest, an extreme environment on Earth. The non-climbing twins remained at lower altitude, including in Boulder, Colorado. Remarkably, the team found similar evidence of oxidative stress and changes in telomere length in the climbers.

Christopher Mason, associate professor at Weill Cornell Medicine and a co-author with Bailey, performed gene expression analyses on the Mt. Everest climbers. He found evidence of a telomerase-independent, recombination-based pathway of telomere length maintenance known to result in longer telomeres.

Bailey said that when chronic oxidative stress occurs, it damages telomeres.

"Normal blood cells are dying and trying to survive," she said. "They're adapting to their new environment. Some cells will activate an alternative pathway to keep their telomeres going. It's similar to what happens with some tumors. Some of the cells emerge from that process. That's what we think we're seeing during spaceflight as well."

Luxton said the mechanism described above—known as alternative lengthening of telomeres, or ALT—was an unexpected finding.

"You usually see that in cancer or in developing embryos," he said.

Similar to conclusions from the Twins Study, Bailey said the new findings have implications for future space travelers establishing a base on the Moon or traveling to Mars, or even as a space tourist. Long-duration exploration missions will involve increased time and distance outside of the protection of the Earth.

Although longer telomeres in space might seem like a good thing, perhaps even a "fountain of youth," the scientist said she suspects a somewhat different ending to the story.

"Extended lifespan, or immortality, of cells that have suffered space radiation-induced DNA damage, such as chromosomal inversions, is a recipe for increased cancer risk," she said.

Bailey said she and the team observed increased frequencies of inversions in all crewmembers, during and after spaceflight.

"Telomeres really are reflective of our lifestyles—whether on or off the planet," said Bailey. "Our choices do make a difference in how quickly or how well we are aging. It's important to take care of your telomeres."

"Fundamental Biological Features of Spaceflight: Advancing the Field to Enable Deep Space Exploration" to be published in Cell.
"Temporal Telomere and DNA Damage Responses in the Space Radiation Environment," to be published in Cell Reports.
"Telomere Length Dynamics and DNA Damage Responses Associated with Long-Duration Spaceflight, which will also be published in Cell Reports.

In a landmark discovery for global wheat production, a University of Saskatchewan-led international team has sequenced the genomes for 15 wheat varieties representing breeding programs around the world, enabling scientists ...

The water-to-land transition is one of the most important and inspiring major transitions in vertebrate evolution. And the question of how and when tetrapods transitioned from water to land has long been a source of wonder ...

An international research collaboration, including scientists from the University of Adelaide's Waite Research Institute, has unlocked new genetic variation in wheat and barley—a major boost for the global effort in breeding ...

To see how deeply interconnected the planet truly is look no further than the massive ice sheets on the Northern Hemisphere and South Pole.

A Cretaceous-age, crow-sized bird from Madagascar would have sliced its way through the air wielding a large, blade-like beak and offers important new insights on the evolution of face and beak shape in the Mesozoic forerunners ...

Monash University researchers have created the world's first bioactive plant-based nanocellulose hydrogel to support organoid growth and help significantly reduce the costs of studies into cancer and COVID-19.

Living at low gravity affects cells at the genetic level, according to a study of worms in space.

Scientists at Sanford Burnham Prebys Medical Discovery Institute have shown that fruit flies that spent several weeks on the International Space Station (ISS)—about half of their lives—experienced profound structural ...

For space exploration to be successful, it's vital to understand—and find ways to address—underlying causes of the health issues that have been observed in astronauts who have spent extended periods of time off world. ...

Mahesh Bandi, a physicist with the Nonlinear and Non-equilibrium Physics Unit, OIST Graduate University, Onna, Okinawa, has found a way to produce N95-type respirator filters that is less expensive and quicker than conventional ...

Publisher Springer Nature has announced an open access option for researchers who do not want their papers locked behind a paywall. Starting in January, Springer Nature will allow researchers to pay for open access publication.

Gamma-ray bursts (GRBs) are the most luminous and explosive transient phenomena in the universe after the Big Bang. A powerful tool for characterizing and classifying GRBs to allow them to be used as tracers of the expansion ...

Exquisitely preserved feeding marks on fossil conifer leaves show that the same insect feeding and fungi persisted for millions of years on the same type of plant, from ancient Patagonian rainforests to the modern rainforests ...

Despite their reputation, rats are surprisingly sociable and actually regularly help each other out with tasks. Researchers at the Universities of Göttingen, Bern and St Andrews have now shown that a rat only has to smell ...

From the splendorous red hues in the Grand Canyon to the mundane rust attacking a neglected bicycle, iron hydroxides are all around us. As a matter of fact, they are just as common as quartz, which is the most widely distributed ...