All the mice that received transplants in both experiments became fertile again, while control mice that had not received transplants did not. In the first experiment the mice resumed normal reproductive cycles that lasted for more than 80 days, and in the second experiment, they lasted for more that 130 days.
Dr Kagawa said: "All the mice in both experiments that had received transplants resumed the normal reproductive behaviour of young mice. They showed interest in male mice, mated and some had pups. Normally, old mice stay in the corner of the cage and don't move much, but the activity of mice that had had ovarian transplants was transformed into that of younger mice and they resumed quick movements. Furthermore, the lifespan of the mice who received young ovaries was much longer than that of the control mice: the mice that had received two ovaries lived for an average of 915 days, and the mice that had received one ovary, for an average of 877 days. The newest of our data show the life span of mice that received transplants of young ovaries was increased by more than 40%.
"The results show that transplanted normal ovaries from young mice can function in old, infertile mice, making them fertile again, but, in addition, extending their lifespan. Women who have ovarian tissue frozen at young ages, perhaps because they are about to embark on cancer treatment, can have their young ovarian tissue transplanted back when they are older. Normally we would be doing this simply to preserve their fertility or to expand their reproductive lifespan. However, our mice experiment suggests that this might also improve overall longevity. Further research has to be conducted before we can know whether or not this is the case."
Dr Kagawa said it was not known why the ovarian transplant increased the lifespan of the mice, but it might be because the transplants were prompting the continuation of normal hormo
|Contact: Emma Mason|
European Society of Human Reproduction and Embryology