Adult fruit flies given a cancer drug live 12% longer than average, according to a study researching healthy ageing. The drug targets a specific cellular process that occurs in animals, including humans, delaying the onset of age-related deaths by slowing the ageing process.
The study published in the journal Cell shows for the first time that a small molecule drug, which limits the effects of a protein called Ras, can delay the ageing process in animals. The treated fruit flies outlived the control group by staying healthier for longer.
Trametinib is used to treat skin cancer and was chosen for its ability to inhibit Ras signalling as part of the 'Ras-Erk-ETS' cell pathway. The role of Ras has been well characterised in cancer but it is also known to affect the ageing process. Previously, the DNA of yeast was changed to reduce Ras activity, which extended lifespan, so the team wanted to explore inhibitors of this pathway in an animal.
Female fruit flies were given trametinib as an additive in their food. A small dose of 1.56 µM, which is approximately equivalent to a daily dose of the drug in a human cancer patients, increased the fruit flies' average life expectancy by 8%. With a higher dose of 15.6 µM, the flies lived 12% longer on average.
To test the anti-ageing properties of the drug in later life, fruit flies over 30 days old that had almost all stopped laying eggs were given the same moderate dose of 15.6 µM, and still had an increased life expectancy of 4%. Flies exposed continuously to the drug from an earlier stage in life lived longer than those who began dosing later in life, possibly indicating a cumulative effect of the drug.
The research suggest it is possible to develop pharmacological treatments to keep us healthier for longer. The researchers' next step is to investigate the effects of targeting the Erk-Ras-ETS pathway in more complex animals, such as mice, with a view to developing a drug regime that could be suitable for testing in humans.