In news sure to shiver exterminators everywhere, scientists at Case Western Reserve University have created a super mouse. A mighty mouse! And not just one -- 500 of them! As a result of genetic engineering that boosts the level of an important skeletal muscle enzyme, these little buggers are markedly more active, more aggressive, fitter, and can breed and live longer than ordinary mice.
Whereas a regular rodent can't last an hour on a treadmill -- a cute little mousey treadmill, naturally, not one you find at Gold's -- the super mice can run five or even six hours at 20 meters per minute. An ordinary female mouse can't have any baby mice after she's about a year old, but the mighty mice can reproduce well past age 2.
Richard Hanson, a biochemistry professor who developed the mice with the help of his mousey grad students, offers this quotable quote in a press release: "They are metabolically similar to Lance Armstrong biking up the Pyrenees; they utilize mainly fatty acids for energy and produce very little lactic acid."
The engineered mice have very high levels of an enzyme called phosphoenolpyruvate carboxykinase, or PEPCK-C. Ordinary mice have only 0.08 units of PEPCK-C per gram of skeletal muscle -- super mice have an amazing 9 units per gram.
As a result, their metabolisms are through the roof. And when exercising, super mice rely on fatty acids for their fuel, while ordinary mice use carbohydrates, which raises the level of lactic acid in their blood.
Alas, the researchers say they're not going to do the same thing in humans. "The ethical implications are such that this approach should not be used in humans, or is it technically possible at this time to efficiently introduce genes into human skeletal muscle, in order to mimic the effect seen in our mice," Hanson says. One wonders if the Defense Department feels the same way. (Or maybe the DoD will just use super mice to go after Iran?)
The mouse study is published in the Journal of Biological Chemistry.
Here's a video of the super mouse in action. The mouse in the back is an ordinary rodent -- watch how quickly he conks out, while the enzymey mouse in front keeps going.
Correction: Earlier I said the super mice ran 20 meters per hour -- that's too slow! It's actually 20 meters per minute, or 1200 meters per hour. Thanks to a reader for pointing that out.