Giving brown fat a green light
The investigators have shown that a lipid (a fat-like substance) called 12,13-diHOME that circulates in the blood signals brown fat cells in mice to fuel up with other lipids, says Matthew Lynes, a Joslin postdoctoral researcher and lead author on a paper describing the work in the journal Nature Medicine . In one experiment, obese mice given low levels of the molecule produced reduced levels of blood triglycerides -- other forms of lipids that can increase risks for heart disease and diabetes in humans. Although the Joslin team hasn't shown that 12,13-diHOME also triggers brown fat activation in humans, the lipid could aid research by acting as a biomarker for the process, notes Yu-Hua Tseng, Ph.D., a Joslin principal investigator and senior author on the paper. Today, researchers in the field must detect brown fat activation by injecting volunteers with tiny amounts of radioactive glucose and scanning them via positron emission tomography (PET), which is a difficult and expe...