Scientists discover cells that feed us fat and sugar

Obesity, considered a global pandemic leading to a host of potentially deadly diseases, was the subject of a scientific study led by researchers at the Cold Spring Harbor Laboratory in the United States. Scientists looking for a biological reason for overeating and reduced physical activity have discovered location of neurotensin-expressing neurons – “fat neuron” – in the brain of a mouse.

This cluster of neurons is located in the nucleus of the amygdala, an almond-shaped brain structure involved in feeling emotions and making decisions. That is, the activity of a single neuronal population regulates “food preference for unhealthy, energy-rich foods,” says the study.

In an interview with the website Medical News Today“Identification of neuronal substrates that mediate overeating may provide new molecular targets for the development of new anti-obesity treatments,” said Alessandro Furlan, one of the study’s authors and now an assistant professor at the Karolinska Institute in Sweden.

Fatty and sugary foods affect the brain

To analyze neuronal behavior, the researchers conducted several experiments with mice. In the first part, they looked at the neural activity of rodents in response to eating normal food or eating a high-fat diet (HFD) after food restriction.

After an HFD, but without eating, the researchers noticed higher levels of activity in an area called the amygdala. Interstitial nucleus of hind limb of anterior commissure (IPAC). Tests have shown that certain neurons in IPAC can be stimulated after consuming more palatable food, but not from an energy deficit.

Finally, the scientists optogenetically activated IPAC neurons, which triggered obesogenic behaviors in genetically modified mice, so-called hedonic eating (compulsive eating). On the other hand, the researchers reduced the amount of eating and “emotional hunger” by inhibiting the activity of IPACs.

ARTICLE – Nature Neuroscience – DOI: 10.1038/s41593-022-01178-3.