April 20 (UPI) -- When naked mole-rats run low on oxygen, they metabolize fructose just like plants, a new study showed.
The brain cells of most mammals, including humans, quickly die when deprived of oxygen, which is why heart attack and stroke can lead to serious brain damage. When naked mole-rats are oxygen-deprived, a unique metabolic pathway throws the species' cells a lifeline.
"This is just the latest remarkable discovery about the naked mole-rat -- a cold-blooded mammal that lives decades longer than other rodents, rarely gets cancer, and doesn't feel many types of pain," lead researcher Thomas Park, professor of biological sciences at the University of Illinois at Chicago, said in a news release.
When researchers exposed naked mole-rats to low-oxygen environments in the lab, they measured a release of fructose into the rodent's bloodstream. Tiny fructose pumps supplied brain cells with the sustaining sugars. Fructose pumps have previously only been identified in the intestine cells of mammals.
"The naked mole-rat has simply rearranged some basic building-blocks of metabolism to make it super-tolerant to low oxygen conditions," said Park.
By slowing their breathing and heart rate, and converting fructose into energy, the naked mole-rats survived for up to five hours in low-oxygen conditions capable of killing a human within minutes.
Naked mole-rats are the first and only mammal species observed using suspended animation to protect itself from oxygen deprivation.
Scientists suggest the species adopted the unique capabilities in order to survive in their crowded, poorly ventilated underground burrows, where oxygen levels fluctuate and can be quickly depleted.
Researchers also found naked mole-rats avoid pulmonary edema, the buildup of fluid in the lungs, another risk of low-oxygen conditions -- one that affects high-altitude climbers.
Scientists published their study of naked mole-rats in the journal Science.