Normally, fat cells store energy. In brown fat cells, however, energy is dissipated as heat - brown fat thus serves as a biological heater. Most mammals therefore have this mechanism. In humans it keeps newborns warm, in human adults, brown fat activation positively correlates with cardio-metabolic health.
"Nowadays, however, we're toasty warm even in winter," explains Prof. Dr. Alexander Pfeifer from the Institute of Pharmacology and Toxicology at the University Hospital Bonn. "So our body's own furnaces are hardly needed anymore." At the same time, we are eating an increasingly energy-dense diet and are also moving far less than our ancestors. These three factors are poison for brown fat cells: They gradually cease to function and eventually even die. On the other hand, the number of severely overweight people worldwide continues to increase. "Research groups around the world are therefore looking for substances that stimulate brown fat and thus increase fat burning," says Pfeifer.
Dying fat cells boost energy combustion of their neighbors
Together with a group of colleagues, the team at the University of Bonn has now identified a key molecule named inosine that is capable of burning fat. "It is known that dying cells release a mix of messenger molecules that influence the function of their neighbors," explains Dr. Birte Niemann from Pfeifer's research group. Together with her colleague Dr. Saskia Haufs-Brusberg, she planned and conducted the central experiments of the study. "We wanted to know if this mechanism also exists in brown fat." [...]