For many years, it is assumed that hormones were the way adipose tissue sends messages related to stress and metabolism to the brain. Neuroscience News reported that the new research from Scripps Research Institute scientists described newly identified sensory neurons that can carry a stream of messages from the fat cells to the brain.
Li Ye, Ph.D., co-senior author of the study from Scripps Research said that the discovery of these sensory neurons suggests that the brain is actively surveying fat cells and not just passively receiving messages about them. Co-senior author and professor Ardem Patapoutian, Ph.D. added that this demonstrates how important sensory neurons are to health and disease.
Eavesdropping in the Communication Between Fat Cells and the Brain
The study, titled "The Role of Somatosensory Innervation of Adipose Tissues" published in the journal Nature, reports that the brain and fat cells are sending direct messages and influence the metabolism of the boy rather than simply responding to hormonal signals in the blood.
Patapoutian and his colleagues at Scripps Research Institute developed two new methods to "eavesdrop" or look into the relationship between sensory neurons and adipose tissue.
First, the team used an imaging approach they call the HYBRiD that uses solvents to dissolve the opaque biomolecules to render tissues transparent and allow them to track the path of the neuron through the fat or adipose tissue.
They found that almost 50% did not relay to the sympathetic ganglia and instead sent messages to the dorsal ganglia, which is a cluster of sensory neurons, Genetic Engineering & Biotechnology News reported.
Next, they used a second technique to see how neurons in adipose worked. The genetic technique was developed by the team and called retrograde vector optimized for organ tracing (ROOT). The technique allowed them to selectively destroy small parts of sensory neurons in adipose tissue.
The Secret of Weight Loss Could Be in the Brain
Researchers observed that the sympathetic nervous system started converting white fat cells into brown fat when the sensory neuron communication is stopped. Science Daily reported that this then burns calories through a mechanism known as thermogenesis that can speed up the fat-burning processes of the body.
The team previously thought that the nerves in adipose tissue belonged to the sympathetic nervous system and it is turned on during stressful times or when the person is exercising. But now they think that the two opposing nerve signals may work together to trigger fat-burning processes while the sensory neuron pathway turns the process off.
Ye explained that the findings suggest that there is not just a one-size-fits-all instruction that the brain sends to the fat. Rather, it is more different than that as these neurons act like a gas pedal and brake for burning the fat.
Adipose tissue in mammals is important because it stores energy in the form of fat cells and releases them when the body uses energy. More so, fat is released when controlling hormones and signaling molecules associated with hunger and metabolism. However, energy storage and signaling are usually mixed up in diabetes, fatty liver diseases, atherosclerosis, obesity, and other diseases.
The findings have profound implications, although the team does not know yet the exact messages the sensory neurons send to the brain from the adipose tissue. It only established the connections and communications the two have that are key to keeping fat healthy.
RELATED ARTICLE: New Signaling Molecule Increases Energy Consumption of Brown Fat Cells, Counteracts Obesity
Check out more news and information on Medicine & Health at Science Times.
