Why a Young Heart May Not Change Aging Markers

The reason for this is not clear, but João Pedro de Magalhães, who studies aging at the University of Birmingham in the UK and was not involved in the study, thinks it may have something to do with the recipient’s immune system. Immune cells circulating in the blood could influence aging markers in newly transplanted organs, he says.

Another possibility is that any potential rejuvenating effects of a young heart are overshadowed by the other aging components of an older body, Poganik suggests. Alternatively, a single organ may not be enough to produce a measurable effect.

Could Older Donor Hearts Still Be Useful?

Poganik hopes the discovery will encourage surgeons to consider using hearts from older donors, many of which are discarded on the assumption that they will not work. Machines used to preserve organs before transplantation are already changing the field, and Poganik is conducting other studies suggesting that these devices may rejuvenate donor livers to some degree.

Biological Age Is More Complicated Than One Number

This study also highlights how complex aging is. How can scientists get a complete picture of an organ’s or a person’s biological age if it appears to be aging on one scale but not on another?

This complexity means scientists are unlikely to discover a single, complete way to reverse aging, Poganik says. “That means every aspect of aging has to go back in time,” he says. Reversing DNA damage, structural damage, and all the other forms of deterioration involved in aging across different cells and tissues would be a huge challenge.

“Some aspects of biological age are probably reversible, and other aspects are probably not,” he says. Sorry, Mr. Putin.