Anti-aging molecule increased fertility in aging mice
The discovery will help in the future in the development of treatments that improve fertility in humans, the scientists said. The study is published in the journal Nature Aging.The researchers found that a naturally occurring compound enhances fertility in elderly female mice. Administration of the compound reverses age-related changes in reproductive cell function. Exploring the mechanisms of anti-aging reproductive therapy will help restore fertility in humans in the future.
The researchers studied the effect on female germ cells (oocytes) in female flies of spermidine. This molecule was first discovered in sperm, but later also found in other living cells. Previous studies on animal models have shown that this substance has anti-aging effects, including, for example, eliminating cardiovascular disease in mice and restoring cognitive function in fruit flies.
The scientists compared ovarian tissues from young and middle-aged mice and found that the concentration of spermidine in them decreases with age. The oocytes in the older mice were of lower quality, and the follicles - structures made of an egg cell and its surrounding layer of epithelial cells - were characterized by degeneration.
The researchers injected some of the mice with spermidine. Analysis showed that in these animals, the oocytes regained the ability to clear cellular debris, and mitochondrial function improved. The researchers sequenced RNA from oocytes from mice of different ages and found that genes associated with cellular energy production and processes that clear cellular debris were expressed differently in young and old mice, as well as in animals that received spermidine.
As women age, immature eggs (oocytes) in the ovaries are destroyed and their total number decreases, making it difficult to conceive either naturally or through assisted reproductive techniques such as IVF.
"Although tremendous advances in fertility treatment over the past few decades have led to dramatic increases in IVF success rates, a woman's age remains a major barrier to success, as IVF cannot counteract the effects of age on the quality and quantity of eggs that can be produced," Alex Polyakov, an inecologist, fertility specialist and co-author of the study.