Transplanted hearts adopt the biological age of their recipients, study shows

A team led by Jesse Poganik investigated how the biological age of donor hearts changes after transplantation. In mice, hearts from three age groups were grafted into hosts of all ages; four to six months later, DNA-methylation profiling showed the grafts’ cellular age shifted toward that of the host. The researchers then examined biopsy material from 11 adult heart transplants at Brigham and Women’s Hospital, where donor-recipient age differences ranged from 8 to 50 years, and observed the same age-matching pattern.

Analysis of electronic medical records for hundreds of recipients revealed that heart-rate, wall thickness and exercise capacity aligned with the recipient’s age rather than the donor’s. Some functional measures suggested older hearts behaved like younger ones in young patients, though not all effects were reversible. These findings could broaden the pool of usable donor hearts by relaxing age-based restrictions.