Pill Turns Slacker Mice into Marathonists: Study
Researchers in the US have come up with a pill that promises to give a typical junk-food snacking couch potato the silhouette of an athlete and the endurance of a marathon runner.
The drug, which mimics the effects to the body of exercise, works on mice at least, according to scientists at the Salk Institute for Biological Studies in California.
Created only for research and not available commercially, the drug works on a mouse’s genetic switch called PPAR delta.
Scientists understood that in genetically-engineered mice, when the switch was permanently activated, it left the mice with a huge level of endurance, turning them into “indefatigable marathon runners.”
“We wanted to know whether a drug specific for PPAR delta would have the same beneficial effects,” said research team leader Ronald Evans of the Salk Institute’s Gene Expression Laboratory.
The first tests failed, however: the oral drug appeared to activate the gene, but the mice did not do better as exercisers unless they were forced to exercise at high levels. Only then was their endurance heightened.
So the researchers took a look at the link between PPAR delta activation and what happens in the muscles during exercise to rev up the body’s long-distance performance capacity.
Knowing that the metabolic regulator activated protein kinase (AMPK) hikes production of adenosine triphosphate (ATP), the energy store in muscles, they found that there was an interaction between AMPK molecules and PPAR delta during exercise.
So they combined manipulating PPAR delta with giving the mice the synthetic protein AICAR that activates AMPK.
The result was what they were looking for – the mice had a big jump in endurance and trimmer bodies, Evans said in a summary of the research.
The AICAR treatment “essentially puts a turbo charge on PPAR delta,” he said.
After determining the linkage, the scientists did the couch potato test. They fed AICAR to untrained mice with the PPAR delta gene activated. After four weeks, and without any previous traning, the mice got off of their stomachs and ran 44 percent longer than mice without either treatment.
“That’s as much improvement as we get with regular exercise,” said Vihang Narkar, a leader of the research team.
Such a medicine could have beneficial effects to treat muscle-wasting diseases, obesity and other metabolic disorders, the scientists said.
They added that the drug would not be useful to athletes – that it can be detected with a test already developed by Evans.Filed under: Arts & Entertainment