What Happens to Our Cells in Space?

Recent research from scientists at the University of California, San Diego (UCSD) has revealed a startling discovery: spaceflight accelerates aging in human hematopoietic stem and progenitor cells (HSPCs). These cells are crucial for our blood and immune systems.

Breakthrough Findings from the ISS

Published in the journal *Cell Stem Cell*, the research utilized advanced AI-driven nanobioreactor systems during four SpaceX resupply missions to the International Space Station (ISS). After the flights, the study found that these cells exhibited a reduced capacity for producing healthy new cells, increased DNA damage, and accelerated aging at their chromosome ends—all markers of rapid cellular aging.

Insights from The NASA Twins Study

Dr. Catriona Jamieson, director of the Sanford Stem Cell Institute at UCSD, noted, "Space is the ultimate stress test for the human body. These findings are crucial as they show that the unique stressors of space—such as microgravity and cosmic radiation—hasten the molecular aging of blood stem cells."

This study builds on previous NASA research, including the notable NASA Twins Study, which observed astronaut Scott Kelly's physiological changes during a 340-day ISS mission compared to his twin brother Mark on Earth. While many shifts reverted post-mission, some changes lingered, raising concerns for future long missions.

Aging Markers in Space-Exposed Cells

In this study, researchers developed an innovative nanobioreactor platform in collaboration with Space Tango, allowing for the culture and analysis of human HSPCs in space. The results showed that after being in space for 32 to 45 days, the HSPCs demonstrated clear signs of aging. The cells became overly active, quickly depleting their resources and losing their abilities to regenerate—an important function for stem cells.

Additionally, the investigation revealed inflammation and mitochondrial stress in these cells. Unused parts of the genome were activated, potentially destabilizing them and impairing immune responses, which could raise the risk of diseases.

Hope Amidst the Damage

The encouraging news? When the space-affected cells were returned to a healthy environment, some damage showed signs of regression. This suggests that, under proper conditions, it may be possible to rejuvenate aging cells.

Implications Beyond Space Exploration

The implications of this research extend far beyond the realm of astronaut health. It unveils new insights into the molecular mechanisms of aging and age-related diseases right here on Earth. Understanding these processes is essential, especially as we embark on longer space missions.

Twyman Clements, president of Space Tango, expressed excitement about sharing this groundbreaking work with the scientific community, emphasizing the collaborative efforts that made it possible.

Future Research Directions

Looking ahead, the research team plans to expand their studies aboard the ISS and conduct astronaut-based research. They aim to monitor molecular changes in real-time and explore potential genetic or pharmaceutical interventions to protect human health in space and on Earth.

Dr. Jamieson concluded, "Space experiments are complex and push the boundaries of science, improving our ground-based research relevance and advancing our understanding of diseases like cancer."