Keeping pigs skinny may be as likely as making them fly, yet researchers say they have found a way to lower their levels of a powerful hunger hormone so they stopped gaining weight.
The scientists blocked production of a hormone called ghrelin, which creates the sensation of hunger. If a similar procedure could be done safely in humans, it may help people fight obesity, the researchers at Johns Hopkins University in Baltimore said in today's issue of the journal Radiology.
The procedure used chemicals to block blood supply to a stomach region, called the fundus, that makes 90 percent of the body's ghrelin. Pigs that underwent the surgery stopped gaining weight, while comparison animals continued to fatten, the study found. Human studies could examine whether the operation could be an alternative to bariatric surgery now done to reduce stomach size, researchers said.
``Obesity is a huge problem, and there are very limited options for people who have exhausted diets and other methods to reduce weight,'' said Aravind Arepally, clinical director of Hopkins's Center for Bioengineering Innovation and Design in Baltimore, in a Sept. 12 in a telephone interview. ``This procedure leaves the stomach's anatomy intact, and just targets the part that produces the hormone.''
Obesity, a condition of being extremely overweight, increases people's risk of heart disease, diabetes, and cancer. Two-thirds of U.S. adults are either overweight or obese, according to the U.S. Centers for Disease Control and Prevention in Atlanta.
Bariatric Surgeries
Doctors are increasingly using another kind of surgery to decrease the size of the stomach, which can reduce the urge to eat, Arepally said. The operations, called bariatric surgeries, have increased more than fivefold in five years, researchers reported last year in the journal Lancet.
Bariatric surgery costs about $25,000. About 177,000 people in the U.S. had the procedure in 2006, according to the American Society for Metabolic & Bariatric Surgery.
Blocking the blood supply to the stomach's fundus might give obese people better control over their eating habits, Arepally said. He tried out the technique, called gastric artery chemical embolization, in six growing pigs, using a toxic chemical to destroy arteries that supplied the fundus.
While those six pigs stopped gaining weight, another two that didn't undergo the procedure continued to fatten, increasing their body weight as much as 8.6 percent. The surgery reduced ghrelin production by as much as 80 percent, Arepally said in the study.
Role in Diabetes
Recent studies suggest that ghrelin may also play a role in the development of diabetes, along with stimulating eating, said David Cummings, a University of Washington metabolism researcher. While blocking the stomach's blood supply may pose risks, its effects on ghrelin might offer benefits, he said.
``If it really drops ghrelin by 80 percent it might be promising for reducing body weight and treatment of diabetes,'' he said today in a telephone interview.
The study was funded by the National Institutes of Health in Bethesda, Maryland.
