Press Release Summary: Scientists are getting a step closer in their ultimate goal of promoting the brown fat lineage as a potential way of counteracting obesity. The hope ist that this research will lead to better ways to treat obesity, especially for people who are overweight because of their genes. Since the production of brown fat can be stimulated in mice, it is not unreasonable to do it in humans as well.
Press Release Body: The quest for the ultimate goal of promoting the brown fat lineage as a potential way of counteracting obesity is getting a step closer.
According to researcher Bruce Spiegelman, PhD, of Harvard University's Dana-Farber Cancer Institute, he believes that obesity treatments promoting the production of brown fat could be a reality in as little as a decade.
"We know that we can stimulate the production of brown fat in mice," Spiegelman said. "It is not unreasonable to think that we can also do this in humans."
Researchers say that new discoveries surrounding a type of "good" fat that promotes the burning of calories could one day lead to better treatments for obesity.
While the more recognizable white fat stores surplus energy, brown fat burns energy to generate heat. That's why newborn babies have brown fat - presumably to help regulate their body temperature. Adults, however, are believed to have little or no brown fat at all.
Over the years, many studies have been conducted about brown fat, in the hope that unlocking the mysteries of the unique fat could result in treatments to speed up metabolism and promote weight loss.
"I really do believe that promoting brown fat growth is a plausible approach to weight control," said Spiegelman. "To me it is attractive because of its simplicity. If more of our fat were brown fat, the mouse studies suggest that we would be leaner and better able to resist obesity."
In previous experiments, Spiegelman and his colleagues identified what he calls a "master switch" in mice, which promotes the production of brown fat.
In their latest animal studies, the researchers showed that the molecular switch, known as PRDM16, regulates the creation of brown fat from immature cells and that knocking out PRDM16 turned them into muscle cells.
"We showed that brown fat and white fat have completely different origins," he says. "Brown fat is derived from muscle. That was a huge surprise."
Moreover, in the second study, researchers from Harvard's Joslin Diabetes Center described a different trigger for brown fat. Yu-Hua Tseng, PhD, and colleagues identified the protein BMP-7, which is known for promoting bone growth, as a growth factor for brown fat.
In mouse studies, the researchers found that mice genetically altered to have no BMP-7 protein had less brown fat as they developed than non-altered mice.
And developing mice treated with BMP-7 ended up with more brown fat than untreated mice and had greater energy expenditures.
According to Tseng, her lab is now studying the impact of long-term BMP-7 induction on body composition of mice.
"The hope is that this research will lead to better ways to treat obesity, especially for people who are overweight because of their genes," Tseng says. "Right now, there are not many good options for these people."
In an editorial accompanying the two studies, obesity researcher Barbara Cannon, PhD, of Stockholm University, noted that while the two studies answer some questions about the production of brown fat, they raise others about the role of BMP-7 and PRDM16 in obesity and weight control.