Hopes for an Age-Old Remedy
WASHINGTON -- A traditional remedy approved in India for lowering cholesterol appears to work, researchers say, and in a way that might lead to the development of improved drugs.
The resin of the guggul tree has been used in Indian traditional medicine for more than 2,500 years, and more recently has been enlisted to fight high cholesterol.
David Moore of the Baylor College of Medicine in Houston found the guggul extract lives up to its reputation.
“It really does lower cholesterol in a number of clinical studies in the Indian literature,” Moore said.
Writing in a recent issue of the journal Science, he said it has been used in Indian Ayurvedic medicine since at least 600 BC to treat obesity and other disorders. Moore’s team found the steroid guggulsterone, the active agent in the guggul extract, blocks activity of the farnesoid X receptor (FXR) on cells.
FXR helps regulate cholesterol by affecting levels of bile acids, which are produced from cholesterol and released by the liver. “Bile acids are the only way that cholesterol has to get out of the body,” Moore said in a telephone interview. “We knew that FXR was a key regulator of cholesterol metabolism.”
Moore wanted to study FXR more, so he looked for compounds known to lower cholesterol whose mechanism of action was not understood. “I spent quite a lot of time clicking around the Internet,” he said. He found guggulsterone, along with niacin--a B vitamin regularly prescribed for cholesterol patients--and red wine.
Red wine and niacin were not strongly enough involved with FXR to interest him, but gugulipid, available in health food stores in the United States, was.
Tests in mice showed guggul extract lowers cholesterol by blocking the effects of FXR. “We put mice on a high cholesterol diet for a week, and measure cholesterol levels in the liver,” said Moore, who worked with colleagues at the University of Texas Southwestern Medical Center in Dallas.
“In normal mice, you feed them cholesterol and the cholesterol level in the liver goes up. But if you feed them cholesterol and give them guggulsterone at the same time, the cholesterol levels stay the same,” he said.
Mice bred to lack FXR did not respond to guggul.
Moore, who with colleagues has set up a small biotechnology company, said it might be possible to more specifically target FXR with a drug. The company has patented FXR. “As a pharmaceutical company, you are not going to be interested in producing something that is already available, but you are going to be interested in producing something that is better,” Moore said.
