Certain cells less common in belly fat of overweight compared to thinner people: study
WebMD News from HealthDay
By Amy Norton
HealthDay Reporter
MONDAY, Dec. 22, 2014 (HealthDay News) -- Certain immune system cells may play an important role in weight control, an early study suggests.
Scientists had known that the immune cells may help ward off obesity in mice. The new findings are the first to suggest the same is true in humans, researchers report in the Dec. 22 online edition of Nature.
The investigators found that the cells, known as ILC2s, were less common in belly fat from obese adults, versus thinner people. What's more, in experiments with mice, they found that ILC2s seem to spur the development of "beige" fat cells, which boost the body's calorie burning.
It appears that these (ILC2) cells don't work properly in obesity, according to senior researcher David Artis, a professor of immunology at Weill Cornell Medical College in New York City.
Exactly why or how that happens is not clear, Artis said, but those are key questions for future research. The ultimate hope, he added, is to develop new approaches to tackling obesity.
It's only in the past few years that researchers have been gaining an understanding of how the immune system affects metabolism and weight control, according to Artis.
That might sound surprising, since the immune system is best known as the body's defense against infections. But it makes sense in evolutionary terms, Artis said.
He explained that while the immune system's immediate job is to fight infection, it's conceivable that some of its components evolved to have the ability to "communicate" with fat tissue during times of adversity, in order to alter the body's metabolism.
"You can imagine it basically telling the fat tissue, 'We're going to be malnourished for a while. Let's adapt,'" Artis said.
An obesity researcher who was not involved in the study said the new research adds to evidence that the immune system is a player in weight control.
"It's really quite intriguing," said Dr. Charles Billington, an endocrinologist at the University of Minnesota in Minneapolis.
The general idea that immune function and metabolism are connected is not new, according to Billington, who is also a spokesman for the Obesity Society. He noted that when people are injured or have an allergic reaction, the body often goes into "hypermetabolism," or revved-up calorie burning.
source : Immune System May Play Role in Obesity
