The results of the study of longevity on fruit flies need to be revised
The results obtained by researchers at the University of Southern California, working under the leadership of Professor John Tower, indicate the need to revise the results of a number of studies on fruit flies devoted to the study of the mechanisms of longevity.
For many years, researchers have used genetically modified lines of fruit flies, whose genes can be activated and inactivated with the hormone mifepristone, an antagonist of progesterone receptors and glucocorticoids. Preparations of this hormone are used in contraception and for termination of pregnancy in humans.
Mifepristone is actively used to study the genetic basis of aging and the influence of individual genes having analogues in the human genome on the life expectancy of fruit flies. When conducting such experiments, the authors had doubts about the neutrality of the hormone itself. The fact is that there is a lot of data according to which reproduction reduces the life expectancy of both fruit flies and other organisms. Therefore, the effect of the sex hormone can have an impact on life expectancy by influencing reproductive mechanisms.
Indeed, they demonstrated that the effect of mifepristone itself reduced the number of eggs laid by drosophila females and increased their life expectancy by 68% (the median increases from 56 to 94 days).
At the same time, mifepristone did not affect the life expectancy of females who did not have sexual intercourse, the level of survival and maximum life expectancy of which even exceeded the corresponding indicators for females for whom the influence of reproduction was neutralized with mifepristone.
According to the authors, the obtained data open up new directions for research devoted to the study of longevity and the identification of genes and mechanisms regulating the compromise between reproduction and life expectancy and potentially having analogues in the human body. Moreover, they point to the need to revise the results of experiments on the study of longevity genetics on fruit flies conducted using mifepristone.
Article by Gary N. Landis et al. The progesterone antagonist mifepristone/RU486 blocks the negative effect on life span caused by mating in female Drosophila published in the journal Aging.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of the University of Southern California:
New Finding May Compromise Aging Studies.
10.02.2015