Scientists have discovered a drug that extended the lifespans of laboratory animals by nearly 25%, raising hopes it might also slow ageing in humans, BBC reported. The treated mice, nicknamed "supermodel grannies" in the lab due to their youthful appearance, were healthier, stronger, and developed fewer cancers than untreated mice. The drug is currently being tested in humans, though it remains uncertain whether it will have the same anti-ageing effects.
The quest for a longer life has been a recurring theme throughout human history. Scientists have long understood that the ageing process is adaptable; for example, laboratory animals live longer when their food intake is significantly reduced. Currently, ageing research is flourishing as scientists aim to uncover and manipulate the molecular mechanisms of ageing.
Researchers from the MRC Laboratory of Medical Science, Imperial College London, and Duke-NUS Medical School in Singapore investigated a protein called interleukin-11. Its levels increase with age, leading to higher inflammation and triggering several biological processes that control ageing.
In their experiments, the researchers first genetically engineered mice to be incapable of producing interleukin-11. In a second experiment, they waited until the mice were 75 weeks old (approximately equivalent to a 55-year-old human) before regularly administering a drug to eliminate interleukin-11 from their bodies.
The results, published in the journal Nature, showed that lifespans increased by 20-25%, depending on the experiment and the sex of the mice. Typically, old laboratory mice often die from cancer, but the mice lacking interleukin-11 had significantly lower levels of the disease. They also exhibited improved muscle function, were leaner, had healthier fur, and scored better on various measures of frailty.
When I asked Prof. Stuart Cook if the data was too good to be true, he responded, "I try not to get too excited, for the reasons you say, is it too good to be true? There's lots of snake oil out there, so I try to stick to the data and they are the strongest out there." He firmly believes it is worth trialling in human ageing, arguing that the impact "would be transformative" if it worked and expressed his willingness to take it himself.
The major unanswered questions are whether the same effect could be achieved in humans and if any side effects would be tolerable. Interleukin-11 plays a role in the human body during early development. Rarely, people are born unable to produce it, which affects the fusion of skull bones, joint health (potentially requiring surgery), and tooth emergence. It also contributes to scarring. Researchers believe that later in life, interleukin-11 drives ageing.
The drug, a manufactured antibody targeting interleukin-11, is currently being trialled in patients with lung fibrosis, a condition where the lungs become scarred, making breathing difficult. Prof. Cook mentioned that while the trials are not yet complete, the data suggests the drug is safe to take.
This approach is just one of many in the quest to "treat" ageing with drugs. The type-2 diabetes drug metformin and rapamycin, which are used to prevent organ transplant rejection, are both actively researched for their anti-ageing properties. Prof. Cook believes a drug would be easier for people than calorie restriction. "Would you want to live from the age of 40, half-starved, and have a completely unpleasant life, if you're going to live another five years at the end? I wouldn't," he said.
