Ovaries Transplanted Into Young Mice Become 'Younger'
Researchers at Harvard Medical School found that older ovaries transplanted into younger mice became molecularly younger, while younger ovaries in older mice became older, in a study that suggests ovaries play a significant role in aging and physiology
In a groundbreaking study, researchers at Harvard Medical School have discovered that transplanted ovaries can adjust to the recipient's biological age. The study, led by Sharif Iqbal, found that older ovaries became molecularly younger when transplanted into younger mice, while younger ovaries became older when transplanted into older mice.
The researchers used mice of different ages, with young mice being around 4 months old and older mice being around 13 months old. They built an 'ovarian clock' based on levels of gene expression and DNA changes that occur with age, and then surgically transplanted ovaries between young and older mice. The results showed that older ovaries placed in younger mice became molecularly younger, while younger ovaries in older mice became older, 4-5 months after the transplant.
One of the most significant findings of the study was that young mice that received ovaries from animals past their natural fertility window were able to give birth to healthy offspring. This suggests that the younger bodies were able to lower the molecular age of the older ovaries. Additionally, transplanting younger ovaries into older mice boosted the animals' overall health, and even lowered the biological age of the brain, liver, and uterus in old recipient mice.
The study also found that older ovaries transplanted into different older mice produced no births, highlighting the impact of the age of ovaries on the rest of the body. The researchers observed that being in an older body increased inflammation in the younger ovaries, while a younger body reduced it in the older ovaries.
## Why it matters The discovery that ovaries can adjust to the recipient's biological age has significant implications for our understanding of aging and physiology. It suggests that ovaries play a greater role in aging than previously thought, and that the age of ovaries can impact the rest of the body. The study's findings could potentially lead to new treatments for age-related diseases, and could also shed light on the complex relationships between aging, physiology, and the female reproductive system.
The study's results are also consistent with recent research that found transplanted hearts shift towards the recipient's age. As Iqbal notes, 'an organ's biological age is not fixed at the time it is transplanted, it responds to the body it lives in.' This challenges our traditional understanding of aging as a fixed process, and suggests that the body has a more dynamic and adaptive relationship with its organs than previously thought.
