By taking a proven migraine drug and experimenting on its potential to temper food intake, scientists have demonstrated how it can be used to reduce body weight in obese mice. The search bodes well for the possibility of repurposing the commonly prescribed drug to combat obesity, and furthers our understanding of the role serotonin plays in regulating our appetite.
The study builds on previous research investigating the ties between appetite and serotonin, a chemical messenger known to impact everything from emotions to motor skills. But its impact on appetite is a complex process involving 15 different serotonin receptors, molecules that detect the serotonin and alter the behavior of cells as a result.
Previous experiments have tested the ways different drugs target these different receptors, but ones that haven't been studied extensively in relation to appetite are triptans. These are common drugs that treat acute migraines and cluster headaches and target a serotonin receptor called Htr1b.
To investigate their potential impacts on appetite and weight loss, the scientists took six prescription triptans and tested them on obese mice on high-fat diets for a period of seven weeks. Two of these drugs had no impact on the food intake of the mice, but four of them led the mice to eat less. One in particular, called frovatriptan, led to an average reduction in body weight of 3.6 percent when administered daily for 24 days.
“We found that these drugs, and one in particular, can lower body weight and improve glucose metabolism in less than a month, which is pretty impressive,” said study leader Chen Liu.
The researchers then engineered mice to be lacking the Htr1b receptor and gave them frovatriptan. In these models, the drug no longer decreased appetite and drove weight loss, confirming that it confers these effects by acting on that particular receptor. The scientists were also able to pinpoint the neurons in the brain that were critical to the way Htr1b regulates appetite.
“We’ve shown that there is real potential to repurpose these drugs, which are already known to be safe, for appetite suppression and weight loss,” said study Liu.
The research was published in the Journal of Experimental Medicine.
Source: University of Texas Southwestern