Animal Models Give Clues to Understanding Anorexia
Researchers studying how mice respond to food restriction are unlocking the secrets of this mysterious disorder
In a new interview, Stephanie Dulawa, professor at the University of San Diego, California, talks about her work on activity based anorexia in rodents. Acknowledging the limits of modelling a psychiatric illness in animals, Dulawa says: “For anorexia, what we can model is the paradoxical response to negative energy balance.”
If the researchers restrict food and provide a running wheel, and isolate the mice, some begin to lose weight and run more, forgoing food even when it’s freely available. This mimics the behaviour of people with anorexia and could be an in-built famine response. “Some people theorise that ABA is that mechanism saying ‘there’s not enough food here, this could be a serious problem, I need to migrate out of this area,’” says Dulawa.
Some discoveries from this research could be useful in treatment:
“the ABA model breaks down if we give mice high-fat food,” says Dulawa. The mice are normally given feed that contains a mix of carbohydrates, fats and proteins. If given high-fat food, the mouse doesn’t go into ABA. “It just eats.” If reflected in humans, a high-fat diet could be key to recovery and one way to avoid relapse.
Like the men studied in the postwar Minnesota Starvation Experiment, when the mice in Dulawa’s lab are permitted to recover, they tend to overshoot their original weight. “So the mice going beyond their original weight might provide a model for early AN recovery. It might help us understand what’s happening in the brain when that’s going on,” says Dulawa.
Dulawa hopes that her research, and that of others, could lead to new drug treatments and a better understanding of anorexia nervosa. “They might change perceptions to be more aligned to the truth, which is that disorders like AN aren’t that different from diabetes or cancer.”