This image shows two fruit flies on a tablet of the anti-aging drug rapamycin. With the help of the small insects, researchers have investigated the effect of biological sex on aging processes.
In western countries in particular, life expectancy has been increasing for decades. On average, women live longer than men, but usually suffer more from age-related diseases and side effects of medication. Researchers from the Max Planck Institute for Biology of Aging in Cologne and University College London have taken a closer look at these gender-specific differences. “Our long-term goal is for men to live as long as women and for women to remain as healthy in old age as men. But for that we need to understand where the differences come from,” explains Yu-Xuan Lu from the Max Planck Institute.
To get to the bottom of this question, the scientists tested the promising anti-aging drug rapamycin on female and male fruit flies. Our picture of the week shows two of these small subjects on a rapamycin tablet that looks huge compared to them. Although fruit flies do not look very similar to humans at first glance, these small insects share some basic biological mechanisms with us. Rapamycin inhibits cell growth and serves as an immune regulator. The drug is usually given in cancer therapy or after organ transplants. In the fruit flies, the researchers were able to observe that rapamycin lengthened the lifespan of female animals and prevented age-related intestinal diseases. The drug improved autophagy in intestinal cells, i.e. the process that breaks down and utilizes waste materials and used cell components in the cells.
However, male fruit flies showed no increase in lifespan or activity, as Lu and his colleagues found. They attribute this to the fact that the basic activity of autophagy in male intestinal cells is already high. Therefore, the drug could not improve her further. These results identify tissue sex as a critical factor in regulating metabolic processes.
“Biological sex can be a determining factor in the effectiveness of antiaging drugs. Understanding the gender-specific processes that determine drug response will improve the development of personalized treatments," said study leader Linda Partridge from University College London.