A scientific team has identified a molecule in the blood that is produced during sports practice and that can effectively reduce food intake and obesity, according to a study published this Wednesday (06.15.2022) by the journal Nature.
The physiological processes underlying the interaction between exercise and hunger are still poorly understood. To change this, the team of researchers focused on understanding how exercise works at the molecular level in order to capture some of its benefits.
“Regular exercise has been shown to help with weight loss, regulate appetite and improve metabolic profile, especially in overweight and obese people. If we can understand the mechanism by which exercise triggers these benefits, then we will be closer to helping.” many people improve their health,” said Yong Xu, a co-author of the study and a professor at Baylor College of Medicine.
“Older or frail people who can’t get enough exercise may one day benefit from taking a drug that can help curb osteoporosis, heart disease or other conditions,” added co-author Jonathan Long of Stanford University. .
The effects of the Lac-Phe molecule in mice
To reach their conclusions, the scientists carried out an exhaustive analysis of the compounds in the blood plasma of mice following an intense treadmill run.
The main molecule induced was a modified amino acid called Lac-Phe, synthesized from lactate (a byproduct of strenuous exercise that is responsible for the burning sensation in muscles) and phenylalanine (an amino acid that is one of the building blocks of proteins).
In mice with diet-induced obesity (fed a high-fat diet), a high dose of Lac-Phe suppressed food intake by approximately 50% over a 12-hour period, without affecting movement or expenditure energetic.
When administered to mice for 10 days, Lac-Phe reduced cumulative food intake and body weight (due to loss of body fat) and improved glucose tolerance.
Horse and human tests
To further their research, the scientists also studied the sharp elevations in plasma Lac-Phe levels following physical activity in racehorses and humans. Data recorded from human exercise showed that sprinting, for example, induced the strongest increase in plasma Lac-Phe, followed by 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.
The team’s next steps include seeking more details on how this molecule regulates its effects in the body, including the brain: “Our goal is to learn how to modulate this exercise pathway for therapeutic interventions,” Xu concluded.
JU (efe, nature.com, med.stanford.edu)