Aging In Orbit: The Twelve Hallmarks As A Bidirectional Bridge Between Spaceflight-Induced Senescence And Terrestrial Geroscience
Our bodies undergo a complex process called aging, characterized by various cellular and molecular changes. Interestingly, the unique environment of spaceflight, with its microgravity and cosmic radiation, appears to accelerate some of these aging processes at a cellular level.
Researchers have found that the changes observed in astronauts, such as alterations in immune cells and epigenetic modifications, mirror many of the “hallmarks of aging” seen on Earth. These hallmarks are fundamental biological processes that contribute to aging, including things like damage to our genetic material (genomic instability), the shortening of protective caps on our chromosomes (telomere attrition), and changes in how our genes are expressed without altering the DNA sequence itself (epigenetic alterations). Other hallmarks include issues with cellular energy production (mitochondrial dysfunction), the accumulation of “zombie cells” that stop dividing but don’t die (cellular senescence), and problems with how cells communicate with each other.
For example, cellular senescence, where cells permanently stop dividing and release inflammatory substances, is a key aspect of both spaceflight-induced changes and terrestrial aging. Similarly, epigenetic alterations, which are changes in gene activity that do not involve altering the genetic code itself, are significantly impacted by space travel.
This striking similarity suggests that spaceflight can act as a unique, accelerated model for studying human aging. By understanding how spaceflight impacts these fundamental aging processes, scientists can gain crucial insights into the mechanisms of aging on Earth and potentially develop and test therapies to slow down or even reverse age-related decline, benefiting both astronauts on long-duration missions and the aging population on our planet.
Source: link to paper