Researchers believe they have identified in mice models a brain region in the amygdala, the brain’s emotional hub, that regulates appetite suppression and activation.
The team found the neurocircuitry controlling appetite loss, called anorexia, says Haijiang Cai, an assistant professor who is a member of the BIO5 Institute and heads up the neuroscience lab at the University of Arizona that ran the study.
Disease-induced inflammation can trigger anorexia, which can negatively impact recovery and treatment success. It is harmful to quality of life and increases morbidity in many diseases, the authors write.
To determine if the specific neurons within the amygdala control feeding behavior, researchers inhibited the neurons, which increased appetite. They then activated the neurons, causing a decrease in appetite.
“By silencing the neurons within the circuit, we can effectively block feeding suppression caused by inflammation to make patients eat more,” Cai says. “We used anorexia for simplification, but for people with obesity, we can activate those neurons to help them eat less. That’s the potential impact of this kind of study.”
Feeding sounds simple, but it’s not, Cai says. People feel hunger either to satisfy nutritional deficits or for the reward of eating something good. Once food is found, we check that it’s good before chewing and swallowing. After a certain point, we feel satisfaction.
Theoretically, different neurociruitry controls each step.
“This circuitry we found is really exciting because it suggests that many different parts of brain regions talk to each other,” Cai says. “We can hopefully find a way to understand how these different steps of feeding are coordinated.”
The next step is to identify the brain region in humans and validate that same mechanisms exist. If they do, then scientists can find some way to control feeding activities, Cai says.
The paper appears in Nature Communications.
Funding for the research came partially from the Brain and Behavior Research Foundation.
Source: Mikayla Mace for University of Arizona
