Ageing: Transfusing blood from an old mouse to a younger mouse causes cellular ageing

The transfusion led an increased number of senescent cells – which accumulate as we get older – in the young mice, suggesting that cellular ageing isn’t just a case of wear and tear

By Chris Stokel-Walker

Transfusing young mice with blood from older rodents quickly triggers ageing, suggesting that cellular ageing isn’t just a case of wear and tear.

There is a longstanding hypothesis that surgically connecting an old mouse with a young rodent causes a transfer of blood that de-ages the older animal. While this benefits the older mouse, the effects on the young donor rodent were less clear.

To learn more, Irina Conboy at the University of California, Berkeley, and her colleagues transfused blood between young and old mice. Those aged 3 months got blood from animals that were approaching 2 years old.

Two weeks later, the young mice had an increased number of senescent cells – cells in the liver, kidneys and muscles that are damaged and stop dividing, but don’t die. These cells accumulate as a normal part of ageing, beginning after a few years of life in people.

Strength tests also revealed the young mice became weaker after receiving the older rodents’ blood.

Overall, the results suggest that senescent cells can be induced in young animals outside of chronological ageing.

“Cell senescence is only part of the process of ageing,” says Conboy. “That opens new horizons and helps explain why senolytics [drugs that clear senescent cells in the body] so far in clinical trials were less successful than people hoped.”

The experiment may also assist researchers who are trying to tackle the health issues of ageing.

“This is a very exciting study that highlights a potential anti-ageing treatment,” says Roman Bauer at the University of Surrey in the UK.

Bauer highlights how previous research suggests that clearing senescent cells from mice rejuvenates their blood. Referring to the Berkeley study, he says: “The research also demonstrates opportunities for senolytics, so drugs that eliminate senescent cells, which we are currently also investigating for cancer treatment.”

Journal reference: Nature Metabolism, DOI: https://doi.org/10.1038/s42255-022-00609-6