A signalling protein stiffens ovaries as they age
Ovaries age faster than most other organs. A new study points to a possible reason: a signalling protein that rises with age makes ovarian tissue progressively stiffer, impairing fertility and hormone balance.
The connective tissue surrounding egg cells in the ovary, known as the stroma, becomes fibrotic with age. This stiffening interferes with egg maturation and disrupts hormonal function. The researchers showed that levels of the protein interleukin-11 (IL-11) rise in ageing mouse ovaries and directly drive this fibrotic process. The study was published in Nature Aging.
Blocking the protein restores function
When the scientists inhibited IL-11 in aged mice, the results were notable. Ovarian function improved, hormonal imbalances were partly corrected, and fertility increased. The stroma remained more pliable and egg maturation proceeded more normally.
IL-11 is a signalling molecule the body normally uses in wound healing and inflammatory responses. At chronically elevated levels, however, it appears to stiffen tissues in ways that cause harm. Similar mechanisms have previously been described in heart and kidney fibrosis.
Implications for reproductive ageing
Ovarian ageing outpaces biological ageing in most other organs. This matters for fertility, but also for hormone levels that affect the whole body. Targeting IL-11 could in theory extend reproductive lifespan or delay the transition to menopause.
The researchers caution that the findings are so far limited to mice. Whether IL-11 inhibition slows ovarian ageing in humans, and whether it is safe long-term, remains to be investigated. The study nonetheless suggests that ovarian fibrosis could be a tractable target for future interventions.
Want to research this yourself?
Search for example:
- interleukin-11 ovarian fibrosis
- ovarian stroma ageing
- reproductive ageing fibrosis