A protein called interleukin 11 (IL-11) appears to play a crucial role in aging, with scientists extending the lifespans of mice by up to 25 percent simply by blocking the molecule’s effects.
Led by researchers from the Duke-National University of Singapore (NUS) Medical School, the team behind the study used genetic engineering to turn off IL-11 production in a sample of mice, while injecting other mice with an anti-IL-11 drug.
Deaths from cancer and tumorous growths were reduced in both groups, while health conditions related to the effects of aging – including chronic inflammation and poor metabolism – were also less common.
“These findings are very exciting,” says clinician scientist and cardiologist Stuart Cook from the Duke-NUS Medical School.
“The treated mice had fewer cancers, and were free from the usual signs of aging 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.”
Interleukin 11 has been of interest to scientists studying the aging process for several years. We know that it builds up in the body as we get older, and it’s linked to increasing levels of inflammation, scar tissue, and overall frailty.
In genetically modified mice, lifespans were extended by 24.9 percent on average. In the mice given drugs after 75 weeks (about the age of 55 in humans), the median lifespan went up by 22.5 percent in male mice and 25 percent in female mice – overall, those animals were living an average of 155 weeks, rather than the 120 weeks of the control group.
That’s likely down to the IL-11 blocking having multiple effects across different parts of the body, say the researchers: reducing potentially dangerous inflammation and helping organs to heal faster after injury, for example.
“The IL-11 gene activity increases in all tissues in the mouse with age,” says Cook. “When it gets turned on it causes multimorbidity, which is diseases of aging and loss of function across the whole body, ranging from eyesight to hearing, from muscle to hair, and from the pump function of the heart to the kidneys.”
This latest study checks a lot of the necessary boxes that aren’t all covered by a lot of previous anti-aging research: It works in both sexes, it promises a lifespan that’s also a healthy one, and it doesn’t come with any obvious side effects.
Clinical trials in humans will be required to confirm whether the findings here apply to us, but potentially we have a mechanism to keep us healthier for longer – and reduce the risk of some of the diseases that go along with old age.
“Although our work was done in mice, we hope that these findings will be highly relevant to human health, given that we have seen similar effects in studies of human cells and tissues,” says biologist Anissa Widjaja, from the Duke-NUS Medical School.
The research has been published in Nature.
