Pill may mimic effects of exercise
Not everyone can exercise. People with muscle-wasting diseases and movement disorders, the frail, the very obese and post-surgical patients are among those who face a significant challenge when it comes to working out.
But what if a drug could stimulate the body into producing some of the same effects of exercise — more endurance and weight control, for example — without running a single step?
Such a pill may be on the way. Several scientists are testing compounds that apparently can do this — and people wouldn’t even have to move at all to benefit.
“Our goal is to understand these circuits,” says Ronald Evans of San Diego’s Salk Institute for Biological Studies. “We are taking this concept and trying to develop a drug that can help us game the system that is naturally activated during exercise.”
Salk scientists have been working since 2007 on a chemical compound, known as 516, that mimics the effects produced by exercise by triggering a specific genetic circuit, “a back door into the exercise genetic network,” Evans says.
Researchers built upon earlier work that identified a gene mechanism that encourages the muscles to burn fat, rather than carbohydrates, much as highly trained elite athletes do.
“There are many reasons why people cannot run or walk or exercise,” Evans says. “If you can bring them a small molecule that can convey the benefits of training, you can really help a lot of people.”
Several other scientists are studying compounds that work differently from 516, but with the same aim: To give the benefits of exercise to people who aren’t able to do it.
Ali Tavassoli, a chemical biology professor at the University of Southampton, has discovered a drug known as compound 14 that works “by fooling cells into thinking they have run out of energy,” Tavassoli says. It does this through a series of molecular actions that spur cells into metabolizing sugar, which produces energy, he says.
Any such drug would require licensing by the U.S. Food and Drug Administration, yet the FDA doesn’t recognize inability to exercise as a drug-treatable illness.
So Evans has targeted 516 for young people with Duchenne muscular dystrophy, an approach he believes offers the best chance for FDA approval. “This (disease) afflicts kids who can’t exercise and ultimately die of muscle wasting, often at a relatively early age, at 15 or 16,” Evans says.
But the drug, now undergoing a human safety study, has “a potentially wide application,” he says, including for amyotrophic lateral sclerosis, Parkinson’s disease and Huntington’s disease, and for “people in wheelchairs.”
Because Tavassoli’s compound breaks down sugar, he says he sees it as a potential treatment for diabetes or metabolic syndrome, a cluster of conditions including obesity, hypertension and high blood sugar high triglycerides and elevated LDL, the “bad” cholesterol.