Fat-Fighting Chemical Holds Promise

THURSDAY Aug. 27, 2009 -- Researchers report that a manmade chemical appears to have the power to turn off fat production, potentially turning it into a weapon against obesity.

Fat mice injected with the chemical, known as fatostatin, didn't get fatter and developed lower cholesterol and blood sugar levels, the research team said.

But don't run out and ask your doctor for a fatostatin shot quite yet. While the chemical holds promise as a "starting point" to develop new drugs, it's not a drug itself, said study co-author Motonari Uesugi, a researcher at Kyoto University in Japan.

Still, there's the matter of those mice who didn't put on extra ounces. "When fatostatin is injected, mice did not get fat even when they ate a lot," Uesugi said. Furthermore, "we did not see any obvious side effects or toxic effects," he added.

Researchers have long been trying to find a pill to help people fight obesity. Anti-obesity drugs do exist, but they have side effects that convince some patients to stop using them.

Uesugi said his laboratory has samples of 30,000 chemicals and is testing them on human and mouse cells. The molecule in question, fatostatin, appeared to stop fat production by turning certain genetic switches.

In the new study, published in the Aug. 28 issue of the journal Chemistry and Biology, the researchers report that the chemical prevented obese mice from getting fatter even when they could eat whatever they wanted.

But Uesugi said injection of a drug isn't a good option for people with chronic metabolic diseases, such as those that cause obesity. More research needs to be done to develop a drug that could be taken by mouth and is safe for people, he said.

In regards to safety, fatostatin's "activity on 63 genes, many of which have nothing to do with fat synthesis, raises questions about potential side effects, particularly if the chemical is ingested over many years," noted Dr. Nicholas H.E. Mezitis, assistant professor of clinical medicine at Columbia University College of Physicians and Surgeons, who is familiar with the study findings.

For the moment, it is "still challenging" to develop drugs that safely treat obesity, said metabolism researcher Dr. Tae-Hwa Chun, who also is familiar with the report.

A positive finding "in cells and rodents does not always lead to the development of safe and effective drugs for patients," added Chun, an assistant professor at the University of Michigan who specializes in metabolic syndrome.

Still, Chun said, there's promise in the idea of targeting genetic switches that turn on fat production, as fatostatin appears to do.

More information

Learn more about obesity from the National Institutes of Health.

Posted: August 2009


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