The immune system contributes to obesity


It was the researchers from the Gulbenkian Institute of Science (IGC), who discovered a new population of immune cells that contribute to obesity, opening a new window for the treatment of the disease, the institution said this week.

These are the cells that destroy norepinephrine, a neurotransmitter (chemical) released by sympathetic neurons (cells of the nervous system) and inducing fat mass reduction.

The team led by Ana Domingos, from the IGC Obesity Laboratory, gave to these specific cells the name of macrophages SAMs.

Macrophages are cells that, when functioning normally, protect the body from infection. But they have been renamed SAMs because they are in direct contact with sympathetic neurons, thus interfering with the loss of adipose mass.

Ana Domingos gave Lusa as a comparison to these macrophages a vacuum cleaner that sucks norepinephrine with a suction tube, the protein SIc6a2, and then destroys it as if it were an incinerator.

This protein was identified after a genetic analysis to the macrophages, by comparison with other very similar cells, said Ana Domingos.

Later, in a mouse experiment, researchers found that obese rodents, either genetically engineered or fed a high-fat diet, had more SAM macrophages than those with normal weight.

Finally, he was able to confirm from analysis to samples of human nervous tissue that the same type of immune cells and the associated mechanism of elimination of the neurotransmitter responsible for fat reduction also exist in people, thus prospecting new treatments for obesity.

According to Ana Domingos, cited in an IGC communiqué, protein SIc6a2, which transports norepinephrine released by neurons to macrophages, is therefore a new therapeutic target, targeting these cells”, which may overcome harmful side effects of various medicines”.

Scientists are still testing the extent to which amphetamines (drugs with harmful effects on the brain) may be beneficial in a more peripheral zone in nerve tissue as they block the action of this protein.

The results of this research, conducted by the Gulbenkian Institute of Science in collaboration with Italian, German and American institutions and the hospitals of Santa Maria and Curry Cabral in Lisbon, were published in the scientific journal Nature Medicine.