The following is an excerpt from a recent study funded by (not performed by) the Brain and Behavior Research Foundation. Click on the link at the end of the excerpt to read the full article.
New research has revealed specific types of neurons that control eating behavior. This basic research about how the body and brain work together has important implications for obesity and metabolic disorders, and possibly also for eating disorders such as bulimia and anorexia nervosa.
A team at the University of California, San Francisco led by Zachary A. Knight, Ph.D., used genetic methods to classify and distinguish various types of neurons that are bundled together in the vagus nerve. One of the most important nerve conduits in the body, the vagus nerve connects the brain with the stomach and intestines, and has long been known to play a central role in the process by which the body regulates feeding behaviors.
“Given how central eating is in our lives, it’s remarkable that we still don’t understand how our bodies know to stop being hungry when we eat food,” says Dr. Knight, whose 2013 BBRF Young Investigator award supported some of his initial explorations of regulatory systems linking the brain and other parts of the body.
Lining the human gut is an extensive array of nerve endings, which are broadly known to play an important role in controlling how much we eat. The new research extends this knowledge but also challenges long-held assumptions. The prevailing belief has been that hormone-sensitive nerve endings in the gut keep track of nutrients we ingest and initiate signaling when we have eaten enough. But until the new study, no one has been able to discern the specific populations of different neuronal types that convey these “satiety” (fullness) signals from the gut to the brain.
“We don't yet know if our research has any connection to eating disorders like bulimia,” Dr. Knight says. “We think that these intestinal receptors [“stretch receptors”] become activated when people overeat. Given that bulimia is associated with binge eating, dysregulation of these receptors could contribute to these conditions.” Research on the newly discovered regulatory mechanism is just getting under way, he stressed.
Click on the link below to read the full publication on the study: