Overview
- The research, posted as a preprint and reported September 28–29, found that hearts transplanted between young and old mice changed DNA-methylation–based estimates of biological age to match the recipient.
- Investigators ran the same methylation tests on 11 archived human heart‑transplant biopsy samples from Brigham and Women’s Hospital and saw the transplanted hearts' epigenetic ages align more closely with recipients than with donors.
- The team measured biological age using DNA methylation and multiple epigenetic clocks across ~320,000 genomic regions and linked some clinical measures such as heart rate, posterior wall thickness, and exercise capacity to recipient age.
- Authors warn the findings are preliminary because the paper is unpeer‑reviewed, the human sample is small, and transplant surgery itself produced inflammatory and other pro‑aging signals that could confound the epigenetic readouts.
- If replicated in larger, peer‑reviewed studies, the work could expand the pool of acceptable donor hearts and build on older parabiosis findings, but mechanisms remain unclear with mitochondrial activity and systemic immune factors offered as possible drivers.