The African naked mole rat, more a plant than rodent?

The African naked mole-rats – or Heterocephalus Glaber – in an interesting turn of events have proven to be able to survive without Oxygen by metabolizing a kind of sugar called fructose same way as plants do; a new study says.

The naked mole rat a hairless and almost blind rodent is found throughout most of Somalia, central Ethiopia, Djibouti and most of northern and eastern Kenya.

They live in large colonies with up to 300 individuals, deeply underground with an extreme oxygen deficit. The entire colony is limited to a single reproductive female which is the queen and at the most three breeding males.

Adults are 3-4 inches long and weigh 30-35 grams. The queen and the breeding males are the largest individuals in the colony.

Naked mole rats are the longest living rodent living approximately 9 times longer than other species. They are known to reach staggering ages of 30 years and in confinement they live up to 28 years.

They mostly feed on a class of plants called geophytic, such as roots, bulbs and tubers all of which are accessible underground.

Lead co-author and a researcher at the Max Delbruck Center for Molecular Medicine in Berlin, Professor Gary Lewin says, “Naked mole-rats can dig tunnel systems spanning up to 12 miles (20 km) through the East African semi-desert. Before they finally reach the roots and storage tubers of desert plants, the diggers may come to a point of absolute exhaustion and have no oxygen left.”

In humans, lab mice, and all other known mammals, when brain cells are ravenous of oxygen they run out of energy and begin to die.

However, naked mole-rats have a contingency plans for such situations, their brain cells start burning fructose, which in turn produces energy an-aerobically, a metabolic process which is only used by plants.

“Under experimental conditions, naked mole-rats tolerate hours of extreme hypoxia and survive 18 minutes of total oxygen deprivation (anoxia) without apparent injury,” the authors explained.

“During anoxia [oxygen deprivation], the naked mole-rat switches to anaerobic metabolism fueled by fructose, which is actively accumulated and metabolized to lactate in the brain.”

“At oxygen levels low enough to kill a human within minutes, naked mole-rats can survive for at least 5 hours. They go into a state of suspended animation, reducing their movement and dramatically slowing their pulse and breathing rate to conserve energy. And they begin using fructose until oxygen is available again. The naked mole-rat is the only known mammal to use suspended animation to survive oxygen deprivation.”

The findings were published in the April 21^st issue of the journal Science.