Scientists have done the unthinkable — they created super-strong, high-endurance mice and worms by suppressing a natural muscle-growth inhibitor.
With the tweaked gene (suppressed inhibitor) out of the way, mutated mice became true marathoners, capable of running faster and longer before showing any signs of fatigue.
In fact, they were able to cover almost twice the distance than ‘normal’ mice, who did not have the inhibitor suppressed. They also exhibited better tolerance to cold.
The breakthrough potentially opens the way to more advanced and effective treatment of age-related or genetics-related muscle degeneration, the journal Cell reported.
The project was a collaboration between researchers at the Salk Institute for Biological Studies, and two Swiss institutions, Ecole Polytechnique Federale de Lausanne (EPFL) and the University of Lausanne.
The scientists found that a tiny inhibitor may be responsible for determining the strength of our muscles, a university statement said.
By acting on a genome regulator (NCoR1), they were able to modulate the activity of certain genes, creating a strain of mighty mice whose muscles were twice as strong as those of normal mice.
“There are now ways to develop drugs for people who are unable to exercise due to obesity or other health complications, such as diabetes, immobility and frailty,” said Ronald M. Evans, researcher at the Salk university.
“We can now engineer specific gene networks in muscle to give the benefits of exercise to sedentary mice,” he said.
Johan Auwerx from EPFL, who led the study, says molecules such as NCoR1 are molecular brakes that decrease the activity of genes. Releasing the brake by mutation or with chemicals can reactivate gene circuits to provide more energy to muscle and enhance its activity.
Salk researchers and their collaborators reported on the results of experiments done in parallel on mice and nematodes.
By genetically manipulating the offspring of these species, the researchers were able to suppress NCoR1, which normally acts to inhibit muscle tissues.