Potential diet drug burns fat, curbs appetite

NEW YORK (Reuters Health) - It sounds almost too good to be true, but a preliminary study in mice suggests that a team of scientists has developed a drug that both suppresses appetite and burns fat.

If the drug, known as C75, has the same effect in people it would allow dieters to feel full on less food while burning through fat stores, researchers report in the current issue of the Proceedings of the National Academy of Sciences Early Edition.

Normally, the body goes into a survival mechanism when caloric intake is too low by slowing down its metabolism and hoarding fat stores. Over time, eating too few calories will reduce a person's metabolism, making it more difficult to burn calories and shed pounds.

But C75 appears to shut down this system, according to researchers from FASgen, the drug's manufacturer, and the Johns Hopkins University in Baltimore, Maryland.

The findings may someday be used to develop drugs to treat people who suffer from obesity and type 2 diabetes. Currently, a drug for humans is still many years away, Dr. Frank Kuhajda, the study's lead author, told Reuters Health.

"After more work is done that involves close collaboration between chemists and biologists, new compounds will be developed. Next, there is safety testing that will take years, followed by years of clinical studies," Kuhajda explained.

He stressed that any drug that is manufactured must be extremely safe, since it will probably be taken by children as well as adults.

In the study, the researchers fed mice a high-fat diet and measured levels of malonyl-CoA--a compound that prevents fat burning. The mice that received abdominal injections of C75 in addition to a high-calorie diet burned about 33% more calories and lost 50% more fat than mice that did not receive the drug despite having similar blood levels of malonyl-CoA.

Overall, the drug led to a sustained weight loss of about 20% of body mass with just a moderate reduction in food intake, the study notes.

To investigate why, the scientists added C75 to cells from both humans and mice and measured its fat-burning capacity. The drug not only prevented malonyl-CoA from blocking the enzyme that burns fat, but actually enhanced its ability to burn fat.

In an interview, Kuhajda said that the findings have important implications for rates of type 2 diabetes, which have soared over the past two decades as Americans have continued to pack on pounds. The disorder is the leading cause of lower limb amputations and kidney failure and a major cause of blindness and heart disease.