Scientists Identify Natural Protein That Mimics The Effects of Exercise in Animals

What if you could get a lot of the benefits of exercise, without moving a muscle? A class of naturally occurring proteins called Sestrins might be able to mimic such metabolic effects, a new study suggests, although so far the results have only been observed in mice and fruit flies.

An instant exercise pill for humans is still some way off then – don't give up your gym membership just yet – but the new findings could further research into helping the physically impaired and injured keep their bodies in healthy shape.The team started with Drosophila flies, fashioning a makeshift insect treadmill in the lab. They compared the running and flying of flies (bred to lack the ability to make Sestrin) against flies bred to overexpress the proteins, and also looked at a normal group of flies.

In a related study on mice, produced in collaboration with some of the same researchers, the overexpression of Sestrin was shown to also help combat muscle atrophy – so Sestrin treatments could potentially be used to protect broken limbs inside casts, for example.

These findings could also be helpful in care for the elderly, the researchers point out, enabling older people who aren't as mobile as they used to be to still get some of the same benefits as they would from hitting the gym twice a week.

"We propose that Sestrin can coordinate these biological activities by turning on or off different metabolic pathways," says physiologist Jun Hee Lee from the University of Michigan.

"This kind of combined effect is important for producing exercise's effects."

The research has been published in Nature Communications.