COURTESY JOSH JENNINGSThe lateral hypothalamus (LH) has for decades been known as a brain region involved in regulating eating. Researchers now describe in Science today (September 26) that activating a cluster of neurons, which reach into the hypothalamus from another region of the brain, turns on “voracious” feeding behavior in rodents. The authors propose that perhaps dysfunction of this circuit drives pathological eating habits in humans. “Both eating disorders and obesity have a neurological basis to them,” said Garret Stuber, lead author on the study and a neurophysiologist at the University of North Carolina, Chapel Hill. “What we would hypothesize is that neural circuit dysregulation in these areas could contribute to eating disorders and obesity.”
The way this brain circuit operates is “completely unexpected,” said Hans-Rudolf Berthoud, a neurobiologist who studies eating pathways at Pennington Biomedical Research Center and who was not involved in the study. Unlike earlier studies that had found activation of LH neurons stimulates eating, this newest report found that turning off LH neurons prompts mice to feed. “I would have never expected that,” Berthoud told The Scientist.
Stuber's group focused on an area of the brain called the bed nucleus of the stria terminalis (BNST), which is known for its role in fear and anxiety. Neurons in the BNST project to a number of areas in the brain, but a sizable proportion head to the LH. So Stuber and his colleagues developed an optogenetic switch to ...
