Dr. Helena Cochemé, who leads the Redox Metabolism Group at MRC LMS, put the practical advantage in numbers. "The fact that we can extend lifespan in yeast, worms and flies is very exciting. Worms and flies in the lab live for around three weeks and three months, respectively, compared to roughly three years for mice, so we can make progress and discoveries much more rapidly and efficiently than in mammalian systems."

The result itself is a first, she said: "Our study is the first demonstration that directly targeting AMPK using a drug can have longevity benefits in living organisms."

Cochemé also offered a simple analogy for how the enzyme works. "AMPK is effectively the body's equivalent to the 'energy saving mode' on a mobile phone. If a treatment works successfully in three such distantly related species, then these results give us more confidence that in the longer term, the effects could translate to mammals and eventually perhaps humans."

Cleaner results, but mice come first

The direct approach has another advantage beyond efficacy. David Carling, who leads the Cellular Stress Group at MRC LMS, explained: "By switching on AMPK specifically using a direct activator, it is possible to achieve a much cleaner result, avoiding potential side effects. Now that we have very solid, convincing evidence from the laboratory model organisms, the next step will be to show that we can also improve health and extend lifespan in mice."

There is also some clinical reassurance already in hand. "Direct AMPK activators have already been used safely in clinical trials for the treatment of specific metabolic diseases," Carling noted. "This opens the door for using AMPK activators to treat a range of human diseases in the future."

Still, anyone hoping for an anti-aging pill should temper expectations. Filipe Cabreiro, who leads the Host-Microbe Co-Metabolism Group at MRC LMS and a laboratory at the University of Cologne, was blunt about the timeline: "The field is still a long way from anti-aging clinical trials in humans. This is because aging is not technically classified as a disease."

The stakes, however, are large. "But improving health in older age would be hugely beneficial from a societal and health care perspective, since aging is a major risk factor for so many diseases, such as heart disease, diabetes, cancer and dementia," Cabreiro said.

He added: "The ability to make individuals healthier for longer, for instance by pharmacologically targeting energy balance through AMPK, would be a major biomedical breakthrough."

Scientists at Queen Mary University of London, the Francis Crick Institute and the University of Lyon also contributed to the research.

What to keep in mind

The findings come from yeast, worms and flies — organisms far removed from humans. Effects in one species do not guarantee the same effects in another, and mammalian studies have not yet shown the same results. Whether the lifespan extension seen here will translate to mice, let alone people, remains an open question that only further research can answer.