Pumping iron
Our bodies resist all our efforts to lose weight. That's a physiological fact.
Put in another way, once our body detects a decrease in calories consumed, human metabolism increases the body's energy efficiency and weight loss is resisted.
A team from the University of Iowa and the Iowa City VA Medical Center has sought to circumvent this defense by developing a targeted approach to override the body's "energy saving" mode and allow muscles to burn more energy even during low to moderate exercise.
The new findings in the journal Molecular Therapy might provide the basis of a therapy that could help people really lose weight by helping overcome the body's natural resistance to weight loss.
These researchers have developed a muscle injection that burns more calories when a person does simple chores or exercises.
They're working on a muscle-targeted injection therapy to assist overweight people lose weight easily, even when low to moderate exercise. This therapy will counter the body's natural tendency to boost its energy efficiency to counter weight loss.
Researchers said that if muscles were less energy efficient, they'd burn more calories even with mild levels of exercise.
"This study shows for the first time that this energy efficiency can be manipulated in a clinically translatable way," said study co-author Denice Hodgson-Zingman, MD, UI associate professor of internal medicine.
The team injected a compound called a "vivo-morpholino" into the thigh muscles of a mouse. The compound suppresses the production of a protein called ATP-sensitive potassium (KATP) channel responsible for regulating the energy efficiency of skeletal muscles. It also determines the amount of energy used by muscles.
Researchers reported the injected muscles experienced protein loss and burned more calories than those that weren't injected as the mouse moved on the treadmill.
"The disruption of the KATP channels results in changes of the muscles' electric properties, which in turn increase calcium turnover," Sivaramakrishna Koganti, a postdoctoral research scientist in Dr. Zingman's lab told Gizmag.
"This change in the calcium handling requires more energy, and thus every time the muscle contracts, it consumes more energy compared to the muscle with the intact KATP channel function."
Interestingly, the injection affected only the muscles in the thigh without impacting neighboring muscles or other organs.
