Imagine if an injection could replace exercise?
Researchers have identified Lac-Phe, an amino acid made up of a combination of lactate and phenylalanine, as a driver of appetite suppression and weight loss.
Article content
Science may be closer to finding a chemical way to replicate the benefits of exercise, as a result of a new study that tries to explain the molecular and cellular reasons exercise is so good for us.
According to a new study published in the journal Nature, researchers successfully reduced both appetite and weight in mice using an injection that replicated a molecule that gets produced in the blood through exercise.
“We wanted to understand how exercise works at the molecular level to be able to capture some of its benefits,” co-author Dr. Jonathan Long of Stanford Medicine told the news outlet at Baylor College of Medicine, one of several institutions that contributed to the research. “For example, older or frail people who cannot exercise enough, may one day benefit from taking a medication that can help slow down osteoporosis, heart disease or other conditions.”
The study’s authors studied the blood of mice who had just finished running on a treadmill. They observed that a modified amino acid with the chemical formula C12H14NO4, called Lac-Phe, was produced in large amounts. Lac-Phe is named after the two compounds that it is made up of: lactate, which is what causes the burning sensation in muscles after intense exercise, and phenylalanine, one of the building blocks of protein.
An ancient system that regulates feeding
Lac-Phe has also been found in high levels in both humans and racehorses who have just finished exercising, as the Baylor article explains. It also seems to be present at the highest levels in the plasma of people who did sprint exercises, followed by people who did resistance training, and then endurance training.
“This suggests that Lac-Phe is an ancient and conserved system that regulates feeding and is associated with physical activity in many animal species,” Long said.
Researchers injected a high dose of Lac-Phe to a group of mice who had been fed a high-fat diet, and found that over a 12-hour period, those mice ate about 50 per cent less than mice in the control group, although they didn’t expend any more energy. After a 10-day period, the mice who got more Lac-Phe ate less, lost more weight and improved their glucose tolerance. And there didn’t appear to be any adverse effects, the researchers found.
Where Lac-Phe didn’t seem to have an effect, though, was in mice who were already lean and healthy. It was also less effective when taken orally than when injected, which, as technology outlet Freethink points out, means it’s unlikely we’ll get an “exercise pill” anytime soon.
Researchers also found that one specific enzyme, CNDP2, appeared to have a major effect on weight as well. Mice who didn’t have the enzyme didn’t lose as much weight as other mice, even with the same amount of exercise.
The next step is to find out more about how Lac-Phe interacts with other parts of the bodies, including the brain, co-author Dr. Yong Xu said. They hope the amino acid can eventually be used to treat conditions including diabetes, osteoporosis and cognitive decline.
