Young Ovaries Extend the Life Expectancy of Old Ovariectomized Mice: Biological and Demographic Implications for Humans

James R. Carey, University of California, Davis
Shelley Cargill, University of California, Davis
Hans Muller, University of California, Davis
Gary Anderson, University of California, Davis

We tested the hypothesis that the input of young ovaries will increase the life expectancy in old ovariectomized (OX) CBA mice by transplanting ovaries from young (2 mo.) donor females into pre-pubertally OX 5-, 8- and 11-mo.-old females. The main finding was that remaining life expectancy at 11 mo. in the 11-mo. transplant cohort was 60% greater than that of the OX control cohort and nearly 40% greater than the intact control cohort. Only 20% of the 11-mo. transplantation cohort died in the 300-day period following ovarian transplantation, whereas nearly 65% of the OX control cohort died during this same period. The longevity response of the mice was strikingly similar to the outcome of experiments on nematode worms where the germ-line cells and/or somatic gonads were ablated. Thus our results suggest that mice and, by extension, other mammals (including humans) can regulate their own aging rate via gonadal signaling.