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Naked Mole Rats Make Like a Plant to Survive in Zero Oxygen

ByAna AcevesNOVA NextNOVA Next

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Naked mole rats are perhaps nature’s most bizarre mammals—and they continue to surprise. We already know that they are impervious to tumors, immune to chronic pain, and can adopt ambient temperature as its own body temperature.

Now, new studies show they can survive in suffocating conditions. Where most humans can last a couple minutes without oxygen, and a mouse will die within 20 seconds, the hairless rodents can survive up to 18 minutes with no apparent neurological damage. Their longevity comes courtesy of a metabolic trick they share with plants.

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Normal atmospheric oxygen levels are about 20%, but Thomas Park and other researchers from the University of Illinois at Chicago observed naked mole rats behaving normally in 5% oxygen levels. They seemed unaware that three-fourths of the oxygen had been removed from their environment. In fact, they remained nonplussed for at least five hours.

Mole rats
Researchers find naked mole rats are unaffected by low-levels of oxygen and can actually survive without any oxygen for up to 18 minutes.

The researchers then lowered oxygen levels even more—all the way down to 0%. Only then did the mole rats stop moving. According to the researchers, their heart rate slowed from 200 beats per minute to about 50. Yet once the oxygen levels returned to a normal state, it was like someone hit “play” on a paused video. The naked mole rats quickly returned to their usual activities.

This wasn’t the first study that showed the rodents surviving on low levels of oxygen, but it was the first to discover how. Naked mole rats’ red blood cells carry oxygen mixed with a viscous version of hemoglobin that boosts the cells’ efficiency. What was surprising though, was the level of fructose molecules present in the oxygen-deprived rodents. Here’s Ben Guarino reporting for the Washington Post:

Using a technique called mass spectrometry, Park and his colleagues analyzed tissue from the mole-rats’ vital organs, including their brains and hearts. They tuned the spectrometer to search for hundreds of different metabolites.

“Boy, that was a big pile of data across the desk,” Park said. But the researchers didn’t need to spend a long time sifting. “The fructose curves just jumped out.”

Naked mole rats have the ability to turn fructose into energy without oxygen, something that humans are only able to do on a very small scale. The only other organisms that rely on fructose so heavily are plants. The researchers aren’t sure exactly where these creatures get fructose—humans, for example, have the mechanism to produce fructose, but it’s typically processed in our livers and turned into fat cells.

What would be even more surprising is if these animals somehow produced their own fructose. To resolve that mystery, researchers need to conduct more studies. But if true, that may just be another strange attribute to these little, hairless critters.