Mice injected with the antibody anti-IL-11 lived longer and suffered from fewer diseases caused by fibrosis, chronic inflammation and poor metabolism – which are the hallmarks of ageing.
An experimental drug that extends the lifespan of mice by 25% could also work in humans, according to the scientist who ran the trials.
The treatment – an injection of an antibody called anti-IL-11 that was given to the mice when they were ‘middle-aged’ – reduced deaths from cancer.
It also lowered the incidence of diseases caused by fibrosis, chronic inflammation and poor metabolism, which are the hallmarks of ageing.
Professor Stuart Cook, a senior scientist on the study, said: “These findings are very exciting.
“While these findings are only in mice, it raises the tantalising possibility that the drugs could have a similar effect in elderly humans.
“The treated mice had fewer cancers, and were free from the usual signs of ageing and frailty, but we also saw reduced muscle wasting and improvement in muscle strength.
“In other words, the old mice receiving anti-IL-11 were healthier.”
Videos released by the scientists show untreated mice had greying patches on their fur, with hair loss and weight gain.
But those receiving the injection had glossy coats and were more active.
The researchers, from the Medical Research Council Laboratory of Medical Science (MRC LMS), Imperial College London and Duke-NUS Medical School in Singapore, gave the mice the antibody injection when they were 75 weeks old – equivalent to a human age of 55 years.
The mice went on to live to an average of 155 weeks, 35 weeks longer than mice who were not treated, according to results published in the journal Nature.
The drug appeared to have very few side effects.
“Previously proposed life-extending drugs and treatments have either had poor side-effect profiles, or don’t work in both sexes, or could extend life, but not healthy life – however this does not appear to be the case for IL-11,” Professor Cook said.
The antibody blocked the action of the IL-11 protein, which is thought to play a role in the ageing of cells and body tissues – in humans as well as mice.