Choking links

High levels of leptin, a hormone produced by fat cells in the body, could explain why obese people develop dangerous blood clots more often than people who are not overweight. The association between obesity and blood clots is well known, but the cause has remained a mystery. Now, new research with mice, conducted by scientists at the University of Michigan (U-M) Medical School, USA, indicates that leptin may be responsible. "Our results suggest that clot formation begins with some type of interaction between leptin and the leptin receptor on platelets -- blood cells which stick together to make clots," says Daniel T Eitzman, a cardiologist at the U-M Cardiovascular Centre.