Researchers Curb Appetites … of Fat Rats

0 Comments | Insight on the News, August 2, 1999 | by Price Joyce Howard

Since the discovery of a "fat gene" five years ago, scientists at the University of Florida have been working to determine whether gene therapy could be an effective treatment for obesity. In June, the investigators announced they have used the technique to control appetite and weight in overweight and normal-weight rats and mice.

"The findings are encouraging ... and testing in humans is not that many years away," says Satya Kalra, a professor of neuroscience at Florida's College of Medicine. He and fellow researcher Sergei Zolotukhin, associate professor of molecular genetics and microbiology, believe that a single injection of genes someday may be a viable -- even routine -- option for treating obesity. "This would be the couch potato's dream. You can eat what you want but stay lean," says Zolotukhin.

Indeed, Kalra suggests that gene therapy could be a "magic bullet," at least for people whose obesity is related to leptin, a protein produced by the obesity gene known as "ob." Leptin helps control weight and food intake by signaling the brain to secrete appetite-regulating signals. The signaling process is believed to be flawed in most obese people, so that even high levels of leptin fail to turn off the hunger signal.

The Florida researchers injected leptin-producing genes into obese mice via a harmless virus that already exists in most adult humans. Once inside the mice, the genes integrated into their cells and produced higher levels of leptin. The animals started losing weight in less than three weeks.