Neural link between early life trauma and binge-eating disorder

Nearly 3 percent of Americans suffer from binge-eating disorder at some point their lifetimes, and of them, more than eight in 10 survived childhood abuse, neglect, or other trauma.

Now, a scientist has identified how early life trauma may change the brain to increase the risk of binge eating later in life.

Researchers revealed how a pathway in the brain that typically provides signals to stop eating may be altered by early life trauma.

The discovery, obtained from studies in mice, in Nature Neuroscience  adds new perspective to behaviors such as binge eating and obesity.

“We wanted to know the mechanism underlying how early life trauma induces these eating disorders,” said the senior author. “What we found is a specific brain circuit that is vulnerable to stress, causing it to become dysfunctional.”

 “We are increasingly aware that early experiences and exposures ranging from those that occur even pre-conception in future parents through those that the fetus experiences in utero and to those that the child experiences throughout postnatal life can have dramatic impact on our health course throughout life. The latest discovery in this one particular case shines an important new mechanistic light on this process. Like all innovative research, the study also raises additional important questions such as whether and how these effects can be changed.”

Stress symptoms can affect our body, thoughts and feelings, and behavior. The finding, the stress on mice who were separated from their litter mates may trigger life-long eating behavior changes.

Binge-eating disorder is marked by recurring episodes of eating more rapidly than normal to beyond a feeling of fullness, and feelings of distress and loss of control, according to the Diagnostic and Statistical Manual of Mental Disorders.

To identify the connection between the disorder and early life trauma, the team studied the impact of a hormone in the brain called leptin. Leptin has long been known suppress appetite and weight gain by signaling the brain that it’s time to stop eating.

The team found that in mice that experienced early life stress and exhibited behavior similar to binge-eating, leptin is less effective in a part of the brain called the lateral hypothalamus, where many behaviors are regulated. Without these signals from the brain, the overeating continues.

Digging deeper, the researchers identified neurons in another part of the brain called the ventrolateral periaqueductal gray that respond to the message from leptin and lateral hypothalamus, thereby regulating binge eating.

“There is much more research to do,” the lead author said, “but by knowing the specific molecule and receptors in the brain to target, we can now provide insight and the foundation for developing therapeutic strategies for the disorder.”