Mixing up the medicine to fight obesity

Graphic: vitamin B12Professor Robert Doyle has been leading a team of interdisciplinary scientists in the search for more effective ways of delivering critical medicines into the body by way of vitamin B12.

Their findings are the subject of a groundbreaking article in the journal Endocrinology (Endocrine Society, 2015). Much of the piece, co-written by Doyle with his collaborator Dr. Christian Roth at Seattle Childrens Research Institute, looks at how B12 interacts with a gut hormone known as YY3-36.

Produced in the intestines, YY3-36 has the distinction of being able to “switch off” hunger by activating a hypothalamic pathway in the brain. For this reason, Doyle and others think YY3-36 could be the magic bullet for anti-obesity medication, but it’s unstable in blood and degrades rapidly in the stomach.

Enter B12. When Doyle combined the nutrient with YY3-36, he found that it didn’t just carry the peptide through the gastrointestinal tract; it enabled YY3-36 to send messages from there, telling the brain it was full.

“These findings demonstrate a stronger, more consistent, and longer inhibition of food intake, following injections of the peptide YY3–36 bonded with vitamin B12,” says Doyle, whose research draws on chemistry and biology. “The work also shows a greater reduction in body weight gain, over the first three days the new drug was administered.”

Doyle’s research is funded by a major grant from the National Institute of Diabetes and Digestive and Kidney Diseases at the National Institutes of Health.