The whale that may hold secret of far longer life
Humans spend fortunes on lotions, supplements and fads that promise to slow aging. The bowhead whale, a giant denizen of Arctic waters, has no such anxieties. It lives for centuries, rarely succumbing to cancer or other ailments that cut our lives short.
How does such a massive creature — weighing some 80 tonnes, with billions upon billions of cells — stay healthy for so long? Could its biology offer humans clues on how to defy age itself? Scientists at the University of Rochester in New York think so. In a study published in Nature, they have identified a protein known as CIRBP that appears to play a key role in prolonging the whale’s life. The molecule — short for “cold-inducible RNA-binding protein” — helps repair damaged DNA, a defence that fends off cancer.
When the researchers added the whale version of CIRBP to human cells, they repaired broken DNA more accurately.
In fruit flies, it even extended their lives.
Professor Vera Gorbunova, who led the study, believes the results could point to a treatment that allows future generations “to live longer than the typical human lifespan”.
With some bowhead whales believed to be at least 250 years old, the species is the longest-lived mammal.
“It’s a superstar of longevity research,” said Dr Alex Cagan, an evolutionary geneticist at the Wellcome Sanger Institute in the UK.
By studying the mammals, scientists hope to untangle a biological puzzle known as Peto’s paradox. Big animals, such as whales, should face higher cancer risks than small ones — simply because they have more cells dividing over longer lifespans. For some reason, or combination of reasons, they do not.
The study found that CIRBP helped to fix the most perilous form of genetic damage, so-called double-strand breaks to the DNA double helix — the structure inside the cell that carries genetic information. Bowhead whale cells perform these repairs both more efficiently and more accurately than those of humans or mice. As a result, its DNA stays pristine for an unusually long time.
Cagan said the findings were “intriguing” and pointed “towards new therapeutic angles that could be explored”.
The clue to why the whales have so much CIRBP may lie in their very cold Arctic habitat. Production of the protein rises when temperatures fall. “If we just lower the temperature a few degrees, cells make more CIRBP,” Andrei Seluanov, a co-author of the study, said.
That detail has sparked speculation.
Scientists were already asking whether mild exposure to chilly temperatures could help protect humans from disease.
If it does, could the human version of CIRBP play a role? “Lifestyle changes — things like taking cold showers — might contribute and might be worth exploring,” Gorbunova said.
Her team’s next steps will include testing whether CIRBP — or drugs that activate its production — reliably and safely improves DNA repair in smaller, shorter-lived mammals.
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