The beloved Karen Carpenter, the other half of the iconic 1970s romantic duet The Carpenters, died on Feb. 4, 1983 from the then-mysterious and mostly unknown disease called anorexia nervosa.

Carpenter died from heart failure caused by complications related to anorexia nervosa. At one time when she was 25 years old, she weighed only 41 kg or 96 lbs.

Her untimely death led to increased awareness of anorexia and other eating disorders. We now know, for example, anorexia can be triggered by disease-induced inflammation, and can negatively impact recovery and treatment success.

Karen’s death at the young age of 32 shone a brighter light on this previously unheard of disease, which today afflicts some three million people worldwide.

Since then, research into eating disorders has multiplied. Recently, researchers from the University of Arizona (UA) claimed they’ve found the neurocircuitry controlling anorexia. A team from the UA Department of Neuroscience believes it’s identified the brain region regulating appetite suppression and activation and it’s found within the amygdala, the brain’s emotional hub.

To determine if the specific neurons within the amygdala control feeding behavior, UA researchers led by assistant professor Haijiang Cai 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,” said Cai. “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.”

He said the circuitry they found is really exciting because it suggests many different parts of brain regions talk to each other. He believes the team can find a way to understand how these different steps of feeding are coordinated.

Cai said the brain region was found in mice models. The next research step is to identify it in humans and validate the same mechanisms exist. If they do, some way must be found to control feeding activities.

The study, entitled "A bed nucleus of stria terminalis microcircuit regulating inflammation-associated modulation of feeding," was published June 24 in Nature Communications.

Cai's co-authors are lead author Yong Wang, JungMin Kim, Matthew B. Schmit, Tiffany S. Cho and Caohui Fang. The research was partially funded by the Brain and Behavior Research Foundation.

Anorexia
Anorexia primarily affects adolescent girls and young adult women. Stefano Pollio/Unsplash