April 8, 2009

Comeback Cholesterol Drug?

Niacin is known to help lower levels of "bad" cholesterol and raise levels of "good" cholesterol, and it gets the job down at a significantly lower cost than other cholesterol lowering medications on the market today.

Unfortunately, the drug, also known as nicotinic acid, is rarely used anymore due to a troublesome side effect. Specifically, it can cause unwanted flushing of the skin that leads to a burning sensation and itching.

Researchers from Duke University Medical Center are working on a possible solution that could once again put niacin on the radar screen for people with high cholesterol. Their research has uncovered the signaling pathway that lead to the flushing seen in some patients.

The pathway goes like this: a protein called beta-arrestin is recruited to a receptor called GPR109A that's known to bind to nicotinic acid. When the investigators eliminated a certain form of beta-arrestin in mice, nicotinic acid-related flushing was significantly decreased.  

The investigators believe it may be possible to design a nicotinic acid drug that binds to GPR109A without stimulating the recruitment of beta-arrestin. The result could be a flush-free medication more people could tolerate.

"This opens up whole new realms for drug discovery," study author Robert Walters, M.D., was quoted as saying. "Not only could it lead to new niacin-based therapies for cholesterol that patients could actually stick with, but it could also mean new treatments for flushing that comes with some types of allergic reactions, hives and other disorders."

SOURCE: Journal of Clinical Investigation, published online April 6, 2009