It sounds too good to be true – but if a new study is anything to go by, the future of working out could be popping a pill and sitting on the couch.
Researchers from Missouri and Florida have developed an injection that tricks muscles into thinking they are working harder than they are and boosting the metabolism.
The new drug – so far only proven to work in mice – targets proteins located in the body’s DNA that turn on genes that control how the body uses energy, which allows for calorie burning without any physical exercise.
Rodents that were administered the medicine for a month weighed less than rodents not given the drug, despite eating the same amount of food. They also had lower cholesterol and burned more fat at rest.
The medicine has not been tested in humans but the mice trials are encouraging. The researchers in Florida and Missouri plan to reformat the treatment as a pill if it reaches human trials
The experimental treatment is in its early stages and still must go through other animal and then human trials, which would take years.
The potential breakthrough is known as an ‘exercise mimetic’ that tricks muscles into perceiving increased energy burning as exercise.
The new drug is called SLU-PP-332.
In addition to reducing fat mass even when mice were kept on a high-fat diet, the injectable also prevented mice from gaining any additional weight over a 28-day period.
It also helped stabilize blood sugar levels.
Dr Thomas Burris, a pharmacy professor at the University of Florida, said: ‘When you treat mice with the drug, you can see that their whole body metabolism turns to using fatty acids, which is very similar to what people use when they are fasting or exercising. And the animals start losing weight.’
They first tested their drug in a group of mice that were made obese by being fed a high-fat diet. Those mice that were administered SLU-PP-332 for 28 days weighed 12 percent less than placebo-treated mice at the end.
And during that time, they had only put on half a gram of fat mass.
Meanwhile, the mice given a placebo injection had gained about five grams of fat mass after that month-long period.
In addition to helping drug-treated mice maintain a lower amount of body fat, researchers also found they had lower cholesterol and triglycerides, a type of fat cells in the bloodstream that is stored in fatty tissue.
Elevated levels of both are usually indicators of an unhealthy diet made up of saturated and trans fats as well as sugary foods and drinks. Obesity is strongly associated with both.
Researchers also tested their drug in mice that were obese to start, not just those who were fed the high-fat diet.
The table shows the results from a 28-day dosing regimen. Mice that were fed a high-fat diet for a month while receiving the new medication gained less than a gram of fat mass (the information on the right) while non-treated mice had gained about five grams (reflected on the left)
Mice that received the injectable (denoted in dark blue) had lower overall cholesterol and lower triglycerides than placebo recipients (in gray). The differences were minor though still statistically significant
Three-month-old obese mice were fed a regular diet and administered either the drug or a placebo for 12 days.
Those mice showed a decreased amount of body fat, also called adipose tissue, even when they still ate the same amount of food.
They also found the mice’s livers weighed less after receiving the treatment.
A heavy liver is an indication that excess fat has taken hold in liver cells, which can lead to potentially severe conditions such as non-alcoholic fatty liver disease estimated to affect roughly 100 million Americans.
Dr Burris said: ‘This compound is basically telling skeletal muscle to make the same changes you see during endurance training.
‘They use more energy just living.’
The drug works by activating Estrogen-Related Receptors on DNA sequences where they play a crucial role in regulating energy usage.
The same team of researchers from University of Florida, Washington University in St. Louis and St. Louis University had previously shown in a mouse trial that their drug increased endurance in mice, which were able to run for 70 percent longer and 45 percent further compared to those who received a placebo.
When certain genes need to be turned on, such as those related to the function of breaking down fatty acids for energy, ERRs bind to DNA. Once those genes are expressed, they increase the body’s capacity for fat-burning.
This is not the first exercise mimetic drug to be tested, but it comes on the heels of breakthrough treatments for obesity hitting the market, including Wegovy and Ozempic, which was first developed to treat diabetes.
The next step will be to test the injectable in more animal models before moving on to human subjects. They also plan to reformat their drug from an injectable to an easy to take pill, though that is still far off.
The team’s findings were published in the Journal of Pharmacology and Experimental Therapeutics.
