In the absence of food, neurons that normally
control appetite initiate complex, repetitive
behaviors seen in obsessive-compulsive disorder (OCD),
and anorexia nervosa, according to a new study by
Yale School of Medicine researchers.
Neural circuits are responsible for flexible
goal-oriented behaviors. The Yale team investigated
how a population of neurons in the hypothalamus that
control food intake are also involved in other
behaviors.
Known as Agrp neurons, these cells also control
repetitive, stereotypic behaviors in mice when food
is not available, the researchers discovered.
The team tested the behavior of mice after the Agrp
neurons were activated. They found that in the
absence of food, mice engaged in repetitive
behaviors, such as grooming and marble burying. They
further demonstrated that these behaviors were
goal-oriented and not related to anxiety.
“These observations unmask the relevance of
primitive brain regions previously linked to eating
to other complex behaviors,” said lead author Dr.
Marcelo Dietrich, assistant professor of comparative
medicine and neurobiology and a member of the Yale
Program in Integrative Cell Signaling and
Neurobiology of Metabolism at Yale School of
Medicine. “These findings are relevant to
understanding diseases with both homeostatic and
compulsive components and highlight the multitasking
nature of neurons in the brain.”
According to Dietrich, the data suggests that these
primitive brain regions play a crucial role in
psychiatric conditions. “The research lays the
groundwork for possible clinical trials to address
the behavioral aspects of anorexia nervosa and other
neuropsychiatric diseases with compulsive behavioral
components,” he said.
Other authors on the study include Marcelo R. Zimmer,
Jeremy Bober and Tamas L. Horvath.
The findings are published in the March 5 online
issue of the journal Cell.
The study was funded by the National Institutes of
Health, the American Diabetes Association, the
Helmholtz Society, The Klarman Foundation and the
Conselho Nacional de Desenvolvimento Cientifico e
Tecnologico, the Brain and Behavior Research
Foundation, and a Science Without Borders fellowship
from CNPq/Brazil.
For more information
Marcelo O. Dietrich, Marcelo R. Zimmer, Jeremy Bober,
Tamas L. Horvath.
Hypothalamic Agrp Neurons Drive Stereotypic
Behaviors beyond Feeding.
Cell, 2015; DOI: 10.1016/j.cell.2015.02.024
Yale
University
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