Fruit flies don’t live very long. Once they hit a month old, they’re not long for this world. But now, according to new work published in Cell, a cancer drug lets them live 12% longer. By targeting a certain cellular process found in many animals (including us), the drug seems to slow down the aging process.
“Death still seems to be inevitable, but we now have evidence to suggest it is possible to develop pharmacological treatments to keep us healthier for longer,” University College London’s Linda Partridge says in a statement. Study coauthor Nazif Alic also of UCL adds: “Our aim is to understand the mechanisms of aging and alter the processes that lead to loss of function and to disease.”
The small molecule drug trametinib has been approved to treat skin cancer by limiting the effects of a protein called Ras, which helps cells grow and multiply. Its overactivation, however, leads to cancerous growth: The Ras proteins of cancer cells are mutated in a third of cancer patients, resulting in uncontrolled cell division, according to the Max Planck Institute for Biology of Ageing. Well, Ras is also known to affect the aging process. Previous work with yeast DNA revealed how inhibiting what’s known as the Ras-Erk-ETS signal pathway extended the lifespan of the single-celled organism.
So what about animals? For this, Partridge and colleagues turned to Drosophila fruit flies, which are reasonably complex, but age more quickly than mammals. To deactivate Ras signaling, the team gave female fruit flies trametinib as an additive in their food. A small dose equivalent to a daily dose for human cancer patients increased the flies’ average life expectancy by 8%. With a higher dose, the flies lived 12% longer on average.
Then, when the researchers offered that same higher dose to fruit flies who were already over 30 days old and had stopped laying eggs, the flies still displayed an increased life expectancy of 4%. Although, they still didn’t live as long as flies who had been exposed continuously to the drug early on -- suggesting how the drug had a cumulative effect. The team didn’t see any adverse effects on their digestive system.
“We were able to extend their lifespan both genetically and by using a cancer drug to target the Ras pathway,” Alic explains, “which provides us with the first evidence for the anti-aging potential of drugs developed to dampen this pathway.” However, the researchers caution against using trametinib as some anti-aging fountain of youth elixir. “That would be mad,” Partridge tells Nature. “We just don’t know enough about the long-term consequences.” Next up, the team wants to investigate the effects of targeting the Erk-Ras-ETS pathway in mice.