Using fat to fight fat
Posted February 6, 2013 8:50 am.
This article is more than 5 years old.
OTTAWA (NEWS1130) – Ground-breaking Canadian research could hold the key to fighting the global obesity epidemic.
Researchers at the Ottawa Hospital Institute are essentially using fat to fight fat. They have discovered a trigger that can turn muscle stem cells into brown fat, a “good” form of fat that acts like a little furnace, pumping up metabolism.
Lead scientist Dr. Michael Rudnicki, director for the Regenerative Medicine Program and Sprott Centre for Stem Cell Research, says brown fat is an energy-burning tissue, important in regulating body temperature .
“Muscle stem cells have long been considered cells that are specialized to make muscle but we discovered that they can make more than just muscle cells,” he tells News1130 from Los Angeles. “They can also make a specialized type of fat cell called a brown fat cell. This the first time that has been conclusively proven.”
“Brown fat cells are a type of fat cell that don’t store fat, rather they burn fat in order to generate heat and keep the body warm. Brown fat is induced and activated by exposure to the cold, normally,” he adds.
It was long thought that human adults carried little to no brown fat, normally found in babies, but people who live outdoors, such as the Inuit years ago or even homeless people, have been found to have significant brown fat deposits and recent studies show average adults carry more than previously thought.
“It doesn’t take very much of it to have an effect — as little as 50 extra grams of brown fat can convert one from being overweight to having more of a slim appearance. It can go through a lot of fat to generate this heat,” Dr. Rudnicki explains.
“Our lab discovered the molecular switch that controls the decision of the muscle stem cell to either become a muscle cell or to become brown fat. We conducted experiments in mice where in one muscle in the leg we encouraged some of the stem cells to become brown fat,” Dr. Rudnicki says they were surprised by the results.
“Even months and months later, these mice were resistant to gaining weight, even when fed a high fat diet, and they were metabolically more energetic, burning more energy. They remained slim and they performed better on tests to challenge their glucose tolerance — they were more resistant to, for example, developing Type 2 diabetes,” he adds.
This raises the possibility brown fat could be harnessed and used for therapeutic intervention in treating obesity in humans.
“Of course this will take many, many years of work to get it towards the clinic, safety issues have to be addressed, but nevertheless, we have identified a totally new pathway that can be manipulated in animals, it’s conceivable that this could also be manipulated using drugs, so I think this a very important advance,” says Dr Rudnicki.
Obesity is now the fifth leading risk of death globally, according to the World Heath Organization. A quarter of Canadian adults are classified as obese.
The research is published in the latest issue of the journal Cell Metabolism.
