Imagine a world where the key to youth and regeneration lies not on Earth, but beyond its atmospheric limits, in the vast expanse of space.
The seemingly far-fetched scenario of a sci-fi movie has become reality in the real world as we explore the intriguing story of Scott, an astronaut who defied the aging process after spending a year in space.
Unearthing the quantum of space-time: is aging relative?
Einstein's theory of relativity, written at the beginning of the twentieth century, has inspired numerous science fiction stories from ‘Planet of the Apes' to ‘Interstellar'. The theory suggests that by traveling at a speed approaching that of light, a body experiences time much more slowly, thus slowing down the aging process. This concept has taken a leap from fiction to reality, as revealed by a study published in ‘Nature' examining the effects of space travel on Kelly identical twins.
Scott, who orbited the Earth for 340 days, and his brother Mark, a retired astronaut, took part in this ambitious experiment to explore the variations undergone by “almost identical genomes” in different environments. The results left the researchers stunned, particularly with regard to the changes observed in Scott's telomeres.
The telomere tale: unraveling the threads of aging
In recent years, scientific research has shown that the length of telomeres – the protective caps on our chromosomes – shortens with time and cell division, ultimately leading to cellular senescence or death. Telomeres, often metaphorically described as the plastic caps that keep shoelaces from fraying, play a crucial role in the aging process and DNA repair.
The shocking revelation came when Susan Bailey, a radiation biologist at Colorado State University, discovered that Scott's telomeres had behaved in the complete opposite way to Mark's over the one-year period. According to the results, Scott's telomeres lengthened during his time in space, contradicting what we previously thought about aging and space travel. But is this surprising discovery linked to a space-age secret, or does it simply offer a better understanding of our body's functions?
The key to immortality? space travel perhaps?
Two possibilities have been suggested. Either this phenomenon is due to factors specifically related to life in space, or it is linked to the lifestyle changes astronauts are forced to adopt. According to Bailey, telomere lengthening may be associated with increased exercise and calorie reduction during the mission. But once back on Earth, Scott's telomeres quickly returned to their original length, indicating that other factors are probably at play.
Further studies showed variations between the two twins in other areas, including DNA methylation, a process that can affect gene expression. As with telomeres, methylation levels returned to normal once Scott returned to Earth. All these results suggest that space travel could affect our bodies in as yet unexplored and potentially revolutionary ways.
Telomeres: the guardians of biological time
Telomeres, discovered in the 1930s, received little attention until recent research revealed their key role in the aging process. Today, researchers agree: if we can reverse telomere shortening, or even lengthen them, we could potentially halt biological aging.
The ‘One Year in Space' mission aims to identify the major changes in the human body caused by a long stay off this planet, in the hope of one day sending astronauts to Mars and beyond. However, the results of the twins' experiment will remain largely confidential due to the sensitive nature of the data. Scott's incredible story of space rejuvenation opens up many exciting perspectives for future research into aging and space exploration, redefining our understanding of life, time and the mysterious aging process.