Study Finds Spaceflight Accelerates Aging of Human Blood Stem Cells

📷WAM

Washington, September 9, 2025 (Saudi Arabia Breaking News) – A NASA-funded study has found that space travel accelerates the aging of blood-forming stem cells, which are vital for maintaining healthy blood and immune systems, according to findings published this month in the journal Cell Stem Cell.

Researchers analyzed stem cell samples flown on four SpaceX resupply missions to the International Space Station between December 2021 and March 2023, comparing them with samples kept on Earth from the same donors.

The study revealed that stem cells exposed to microgravity and increased radiation in space lost some of their ability to generate healthy new cells, became more vulnerable to DNA damage, and showed signs of accelerated aging at chromosome ends.

These blood-forming cells, known as hematopoietic stem and progenitor cells, produce red blood cells, white blood cells, and platelets in bone marrow. Dysfunction in these cells can weaken the body’s ability to repair tissues, fight infections, and guard against cancer, ultimately reducing lifespan.

During spaceflight, the cells became overactive, exhausting their ability to rest and regenerate. They also exhibited mitochondrial stress, inflammation, and activation of “dark genome” sections normally kept silent to preserve cell stability.

Lead researcher Dr. Catriona Jamieson, professor of medicine at the University of California San Diego and director of the Sanford Stem Cell Institute, said: “Stem cell regenerative capacity was diminished but with some variability between donors, suggesting that resilience factors are activated in some individuals but not others.”

Jamieson added that the findings could inform strategies to protect astronauts on long-duration missions and offer new insights into human aging and cancer on Earth.