A drug that inhibits inflammation helped mice live longer and reduced the animals’ incidence of cancer and age-related health problems
Scientists at the Medical Research Council Laboratory of Medical Science and Imperial College London have discovered that ‘switching off’ a protein called IL-11 can significantly increase the healthy lifespan of mice by almost 25%.
The scientists, working with colleagues at Duke-NUS Medical School in Singapore, tested the effects of IL-11 by creating mice that had the gene producing IL-11 (interleukin 11) deleted. This extended the lives of the mice by over 20% on average.
They also treated 75-week-old mice – equivalent to the age of about 55 years in humans – with an injection of an anti-IL-11 antibody, a drug which stops the effects of the IL-11 in the body.
The results, published in Nature, were dramatic, with mice given the anti-IL-11 drug from 75 weeks of age until death having their median lifespan extended by 22.4% in males and 25% in females. The mice lived for an average of 155 weeks, compared with 120 weeks in untreated mice.
Previously, scientists have posited that IL-11 is an evolutionary hangover in humans, as while it is vital for limb regeneration in some animal species, it is thought to be largely redundant in humans.
However, after about the age of 55 in humans, more IL-11 is produced and past research has linked this to chronic inflammation, fibrosis in organs, disorders of metabolism, muscle wasting (sarcopaenia), frailty, and cardiac fibrosis. These conditions are many of the signs we associate with ageing.
While small doses of inflammation can protect us from disease or injury, excessive amounts damage cells, which is believed to accelerate ageing.
The drug used in this study not only increased lifespan but also reduced cholesterol levels, frailty and body weight in the treated animals, and it improved their muscle strength and metabolism. Together, these findings suggest that blocking IL-11 may minimize age-related health declines in mice as well as improving lifespan.
Few approaches have been shown to robustly increase life span in mice by more than 20%, and now IL-11 inhibition adds to that small selection of interventions. As reported, IL-11 inhibition may work through essentially the same pathways as mTOR inhibition. The degree of life extension is similar to that achieved via mTOR inhibitors such as rapamycin. (from “Fighting Aging”)
