In what they call a “stunning research advance,” investigators at Georgetown University Medical Center have been able to use simple, non-toxic chemical injections to add and remove fat in targeted areas on the bodies of laboratory animals. They say the discovery, published online in Nature Medicine on July 1, could revolutionize human cosmetic and reconstructive plastic surgery and treatment of diseases associated with human obesity.
In the paper, the Georgetown researchers describe a mechanism they found by which stress activates weight gain in mice, and they say this pathway − which they were able to manipulate − may explain why people who are chronically stressed gain more weight than they should based on the calories they consume.
This pathway involves two players − a neurotransmitter (neuropeptide Y, or NPY) and the receptor (neuropeptide Y2 receptor, or Y2R) it activates in two types of cells in the fat tissue: endothelial cells lining blood vessels and fat cells themselves. In order to add fat selectively to the mice they tested, researchers injected NPY into a specific area. The researchers found that both NPY and Y2R are activated during stress, leading to apple-shape obesity and metabolic syndrome. Both the weight gain and metabolic syndrome, however, were prevented by administration of Y2R blocker into the abdominal fat.
“We couldn’t believe such fat remodeling was possible, but the numerous different experiments conducted over four years demonstrated that it is, at least in mice; recent pilot data also suggest that a similar mechanism exist in monkeys as well,” said the study’s senior author, Zofia Zukowska, M.D., Ph.D., professor and chair of the Department of Physiology & Biophysics at Georgetown University Medical Center.