Researchers from Columbia University Medical Center found that a once-daily pill that prevents the release of serotonin in the digestive system cured osteoporosis in mice and rats.

The research was published on Nature Medicine's website on February 7, 2010. The findings are important—despite the fact that the study involved only rodents. The research team believes that the results could lead to the development of treatments that actually build bone. Most osteoporosis medications available today only prevent bone loss.

Serotonin—Not Just in the Brain
When most people think of serotonin, they think of its function as a brain neurotransmitter that regulates mood. However, the great majority of serotonin—95%, in fact—is located in the gut. And its function in the gut is much different than its function in the brain.

It was only recently that scientists discovered that the primary role of serotonin in the gut is to prevent bone formation. In a November 2008 issue of Cell, Dr. Gerard Karsenty (who is also the lead author of this Nature Medicine study) published findings that showed that regulation of serotonin release in the gut will affect the formation of bone. It was that major discovery that inspired this study.

An Investigational Drug that Could Be a Breakthrough
In this study, Dr. Karsenty and his team administered a small dose of an oral investigational drug, known as LP533401. The medication prevents the release of serotonin in the gut. The researchers administered the once-daily drug to mice and rats that had post-menopausal osteoporosis. The results showed that the drug fully cured osteoporosis in the rodents.

Additionally, the drug did not affect serotonin levels in the brain. What this indicates in that the medication was not circulated in the blood—and that prevents many side effects.

Dr. Karsenty and his team are enthusiastic about the potential of these findings, but they emphasize that the study was only performed on rodents. Human studies are needed to confirm the legitimacy of these results.

"New therapies that inhibit the production of serotonin in the gut have the potential to become a novel class of drugs to be added to the therapeutic arsenal against osteoporosis," Dr. Karsenty said. "Using these findings, we are working hard to develop this type of treatment for human patients."

To learn more, you can access the full study via this link.