Are mole rats immortal?
Updated: Dec 12, 2021
That’s right, naked mole rats may be the true underlords of this planet, shriveled immortals lurking beneath our feet, sewing discontent throughout society until humanity is on the verge of collapse. Explains the current state of the world quite well, I’d say. But unfortunately we can’t pin humanity’s failings on the machinations of mole rats. We may, however, learn how to extend our misery indefinitely by studying their apparent agelessness. elifesciences.org/articles/31157
Researchers at Google’s creepy biotech company Calico have discovered that mole rats break a basic rule of mammalian aging and could theoretically live forever. Biologist Rochelle Buffenstein has found that naked mole rats break the Gompertz-Makeham law - Discovered in the 1800s by British Benjamin Gompertz, it states that mammalian risk of death increases exponentially with age. So the older we get, the more likely we are to age. According to the model, the risk of dying doubles every eight years after the age of 30.
I just turned 40, by the way.
The rule applies to any mammal scientists have studied, except mole rats. Buffenstein at Calico found that the risk of death for mole rats stays pretty constant no matter their age at about 1 in 10,000.
“If you look at any rodent aging study, a hundred animals is all you need to see Gompertz aging,” she told Kai Kupferschmidt of Science. “Here we have 3,000 data points and we’re not seeing it.”
So a young spry mole rat has the same chance of dying as a middle aged mole rat. She’s been collecting data for more than 30 years (long before Google was a thing) and has more than 3,000 data points. The oldest mole in her experiment is now 35 and seems to be in good spirits. For a mole rat.
So there seems to be good mathematical proof that mole rats don’t age. Also, female mole rats don’t show any signs of menopause and can reproduce late into their lives. Their brains, hearts, and bones appear to remain healthy over time and they rarely get cancer. Buffenstein calls the mole rat “a non-aging mammal.”
For such a small animal, that’s crazy. There’s typically a strong correlation between body size and lifespan - hamsters live for about three years, but elephants can live longer than 50. If you plug mole rat weight of just 35 grams into the formula, you get 6 years. Not 30 plus.
Naked mole rats don’t appear to feel pain the way most mammals do, and only a few individuals out of the hundreds studied are known to have developed cancer. They can also hold their breath for 18 minutes at a time with no apparent side effects whatsoever. Naked mole rats, on the other hand, are relatively safe in the wild once they’ve established a burrowed colony. Predators can’t easily slither into their labyrinthine underground homes, and the mole rats mostly feast on roots and tubers, meaning they hardly ever have to leave the house. The queen mole rat, much like a queen bee, is guarded by a plethora of worker rats. Evolutionarily speaking, that means traits related to longevity could be selected for over traits that allow fast reproduction. “There’s something special about mole rats,” says Braude. “But you want to make sure you get right what’s special, or you’re not going to be looking in the right places for further relevant, cool biology.”
Scientists will need to study a lot more geriatric mole rats to see if the mortality risk does indeed remain fixed across a larger population.
It mostly likely has to do with the animal’s telomeres, Braude says. Telomeres are like the cap on a new pen. They protect strands of DNA from damage or decay. But telomeres themselves get damaged over the lifecycle of a cell, as it makes copies of itself. Once the telomere is gone, cells can no longer create new tissue. This highly scientific, molecular process is more commonly known as aging, and it’s something that the billionaire founders of Google (and Amazon and PayPal) would like to put an end to.
“Naked mole rats appear to be able to protect their telomeres,” says Braude. “They can have many more cell cycles, and that’s a really cool trick.” Scientists still don’t know how or why naked mole rats’ cells have this ability, but it is likely the next step in further research.
But given the fact that Sergey and Larry just turned 44 and I know what it feels like to be middle aged, I’d say there’s a good chance some sort of treatment will be developed in the coming decades.