We’ve seen a number of encouraging developments in recent times related to research into turning calorie-storing white fat cells into heat-generating brown fat cells as a potential weapon in the fight against obesity and related diseases, such as diabetes. The latest news comes out of Ohio State University where researchers have reduced the amount of belly fat in mice by 20 percent by injecting a tiny capsule containing brown fat cells into their abdomens.

The capsules used in the study contained brown fat thermogenic cells, which burn fat to generate heat, that were combined with genetically modified cells that were missing an enzyme that leads to the growth of abdominal, or visceral, fat. Abdominal fat surrounds the internal organs and is linked to a higher risk of type 2 diabetes, cancer and heart disease. These cells were placed inside a capsule that allowed for the release of its contents without triggering an immune response.

When the capsules were injected into the abdomens of the mice subjects, the researchers found that the injected cells acted like “missionaries” that converted existing abdominal white fat cells into heat-generating brown fat cells. This resulted in an initial dramatic 10 percent weight loss.

Although the mice regained some weight over time, the researchers then found that the mice saw a reduction of roughly 20 percent in the amount of abdominal fat. The mice also resisted any dramatic weight gain when placed on a high-fat diet and burned away more than a fifth of the white fat cells that make up their abdominal fat.

Importantly, the amount of subcutaneous fat, which is found just beneath the skin and aids in regulating the body’s temperature by forming an insulating layer, remained unchanged.

“We observed the mice for 80 days after injection and the capsule didn’t break or cause any scarring or inflammation,” said Ouliana Ziouzenkova, assistant professor of human nutrition at Ohio State University and lead author of the study. “This suggests it’s a clean, safe potential therapy for obesity.”

Although studies in larger animals will be needed before human trials could begin, Ziouzenkova said any future therapy based on the research would be best suited to patients who develop abdominal fat with aging and aren’t able to exercise and shouldn’t dramatically reduce their calorie intake as it could result in a reduction of beneficial subcutaneous fat.

The team's research is published in the journal Biomaterials.