Researchers from Australia have developed a pill that can produce 'exercise-like' results on muscles and metabolic health in mice.
With further study and human trials, the team says the new drug might provide a way to combat heart disease by triggering the body to burn fat and improve cardiovascular health – but it doesn't seem to promote weight loss or muscle building.
"Heart disease is still the biggest killer of people with diabetes and obesity, with little in the way of treatment," said team member Sean McGee from Deakin University in Melbourne.
"We have identified a drug that makes the body respond as if it has exercised, with all the fat burning and cardiovascular benefits, which opens up exciting possibilities for future treatments."
To develop the drug, the team first looked at how exercising caused the mice's bodies to burn more fat. In the end, they found that the mechanism inside mice's muscles that turns on the systems responsible for fat metabolism is all controlled by a single protein.
Knowing this, the team genetically manipulated this protein, giving them the ability to turn fat metabolism off and on and found that – even without moving – the mice's muscles appeared to have been exercised and their metabolisms sped up as well. This gave them the idea to see if they could induce this state with a drug.
As McGee says of the findings:
"We then identified a drug that acted in a similar way to what the genetic modification was doing and when we introduced it to mice not only did all the genes that are normally responsive to exercise turn on, the mice ran much longer on an exercise treadmill, burned more fat, had a decline in blood lipids (fats), some of which are associated with cardiovascular disease and diabetes, and their blood glucose levels reduced as well."
The weird thing about the drug, the team says, is that it caused the cardiovascular health of the mice to improve, though it didn't have any effect on weight. Instead, possibly because of the increased metabolic rates, the mice ate more food than before.
"The mice actually tended to eat a little bit more which isn't really surprising because we know that exercise alone is not that effective at making you lose weight, which is more associated with dietary changes," McGee added.
"What we do know is that the mice that received the drug over extended periods were metabolically much healthier than those not taking the drug."
This means that if the drug passes human trials and performs the same way it did in mice, it would provide some of the major benefits of working out, such as improved cardiovascular functioning and a high metabolic rate, but wouldn't be a weight loss pill or appetite suppressant.
With that in mind, the drug will likely be aimed at people who either cannot work out due to physical issues or are at risk of heart disease. Basically, they hope that the new drug might offer a stepping stone for people with health issues to get back into workout shape.
"This could be for frail people who can't exercise but are at risk of cardiovascular disease, diabetes or metabolic disease or patients with obesity who struggle to exercise, where the drug would allow them to find that initial exercise program easier to get into," McGee said.
It's important to explicitly point out, though, that the team's current findings are strictly based off how the drug has worked on mice, meaning that it might not work with humans in the same way. The team hopes to move on to human trials in the near future to verify their results, but only time will tell whether it works as well for us as it does for rodents.
The team's findings were published in the journal Cell Reports.
Update 21 September 2016: We've made a few clarifications to the headline and body of the story to clarify that this drug would be used to improve heart health, not encourage performance enhancement.