The study, published in the scientific journal Nature and was tested in mice and had the contribution of immunologist Henrique Veiga-Fernandes, co-director of the research line at Centro Champalimaud, in Lisbon, and researcher Ana Filipa Cardoso, first author of the article and who did her postdoctoral studies in the immunophysiology laboratory led by Veiga-Fernandes.
"We discovered that the nervous system and the immune system work together so that we can burn the extra fat that we accumulate in our body", Henrique Veiga-Fernandes told Lusa, stressing that the work "establishes a new paradigm for understanding obesity , demonstrating that the 'conversation' between the nervous system and the immune system is crucial for maintaining a healthy weight and reducing the risk of developing diseases associated with obesity, such as cancer". In the experiment with mice, the researchers found that neurons (cells of the nervous system) communicate with a certain type of immune cell that exists in the adipose tissue, the innate lymphoid cells of type 2 (ILC2), through other cells, the mesenchymal.
This communication obeys a "voice of command", given in a region of the central nervous system, near the base of the brain, called the paraventricular nucleus of the hypothalamus, which controls several processes, including metabolism, reproduction and gastrointestinal and cardiovascular functions, which are necessary in communication.
The communication "starts with neuronal signals for the MSCs [mesenchymal cells]. They then send a message to the ILC2, to which the latter respond by ordering the fat cells to speed up their metabolism", describes Ana Filipa Cardoso, quoted in the statement. To Lusa, Henrique Veiga-Fernandes explained that the team was able to "test the real impact of neuroimmune interactions on adipose tissue" by administering to the mice "high-calorie diets".
"The results were extraordinary: When the nervous system and the immune system don't understand each other, mice get obese very quickly," he said.
In the study, scientists genetically manipulated rodents to activate and deactivate the neuroimmune "dialogue" between the nervous and immune systems. Having identified "the chemical, cellular and molecular signals that allow the nervous and immune systems to talk to each other" it will be possible for scientists to interfere in the "conversation" in order to "burn" fat "more efficiently", according to Henrique Veiga-Fernandes .
"This is a huge step towards reducing the risk of developing many types of cancer [such as breast cancer and colorectal cancer]," he said. According to the immunologist, the discovery made, however, raises a new question: how does the brain decide to "talk" to the immune cells of visceral fat, which accumulates in the belly and is bad for health when in excess. "Is the growing sedentary lifestyle responsible for the lack of dialogue? Could certain diseases, such as cancer, disturb and change this decision?", asks Henrique Veiga-Fernandes, launching new avenues for investigation.