Mayo researchers ID possible way to treat obesity

ROCHESTER, MINNESOTA– Mayo Clinic researchers have located a key biological response in muscles that controls energy consumption, a breakthrough that could help obese people lose weight.

In a study published in the journal Cell Metabolism, scientists from Mayo, University of Iowa, University of Connecticut and New York University say potassium (KATP) channels help regulate the way the body burns fat by monitoring levels of adenosine triphosphate (ATP) in cells and adjusting skeletal and muscle activity accordingly.

Normally, KATP is a defensive mechanism, allowing the body to conserve energy in times of environmental stress or food shortage. But KATP can work against obese people who can’t engage in physical activity. The result is a double whammy of sorts: Obese people can’t exercise because of their weight. At the same time, they gain even more weight because KATP channels instructs their cells to store energy.

If researchers find a way to control KATP, the body will burn energy instead of storing it, helping obese people to lose weight AND give them physical stamina to exercise more.

“While mechanisms that preserve energy are naturally protective, they promote obesity in a sedentary, modern society,” says Alexey Alekseev, a Mayo Clinic electrophysiologist and first author of the study. “Our findings suggest that therapeutic targeting of the KATP channel function, specifically in muscle, could offer a new option for obese patients with lower capacity for exercise.”

In the study, the researchers genetically modified mice to shut down their KATP channels. After as early as five months of age, these mice were leaner than normal mice and stayed that way for the duration of their lives.

“By sensing cellular energy content, KATP channels continuously, at any activity level, optimize energy use and define the balance between energy availability and consumption,” Dr. Alekseev said. “In principle, a positive energy balance favoring weight gain could be reversed by targeting muscle KATP channels to control obesity in patients with low to moderate exercise capacity imposed by the overweight state.”