Mouse Cells May Lead to Treatment for Eating Disorders

A group of scientists has recently discovered that a small network of cells in mice can turn appetite on and off, and may possibly lead to a breakthrough in treating eating disorders.

"This was an accidental discovery," lead study author David Anderson, of the California Institute of Technology, told The New York Times.

The remarkable find, described in the journal Nature Neuroscience, may help scientists better understand and treat eating disorders.

In the experiment, Anderson and his team used a technique called optigenetics, which requires genetically manipulating specific cells to make them sensitive to light at a certain wavelength - in this case researchers used blue light. Fiber-optic cables are then inserted into the brain, and when the light is turned on, neurons can be activated or turned off.

What they found was unexpected. A mouse busily munching on some food abruptly stops chowing down after a light signal is sent to its brain, and walks away, no longer interested.

Because the researchers had expected the signal to cause fearful or anxious behavior, "this was really a surprising result," Anderson told The Times.

When they activated the neurons, appetite was turned off, and vice versa.

Anderson had previously studied this same small group of neurons, located in a part of the brain called the amygdala, and found that the area was strongly associated with fear.

The researchers speculate that the mice's reaction could be because the animals were frightened or anxious, so they stopped eating. It's also possible that this group of neurons was activated by bad tastes and "visceral malaise" - feeling nauseated - both of which would have caused the rodents to lose their appetite.

But, Anderson and his colleagues conclude that this small group of neurons might be an appetite-control hub. It may very well be that humans' appetite works in the same way. Scientists already know that the amygdala is associated with emotions like fear, and emotions are strongly linked to appetite.