Is there a brain-switch that tells you you’re full?

The brain works in many ways to communicate back and forth with the body. One of these communication channels concern the fullness level we feel before and after we eat. Typically it was thought neurons were solely responsible for telling the brain to stop eating. However, scientists have discovered that astrocytes, cells that communicate with and maintain the neurons the most, are key components to control appetite. 

Astrocytes are the switches of the brain

Once you’re done with your meal, the glucose spike in the body makes its way to the astrocytes, which then signals to the brain that fullness has been achieved. A collaborative research from the University of Concepción in Chile and the University of Maryland has revealed that the region of the brain that controls hunger and fullness, hypothalamus, has a different signaling pathway than previously thought. 

This signaling pathway can be considered the “switch”. The rising glucose levels are reported by tanycytes (glucose monitoring cells) to the astrocytes, and then to neurons to handle appetite appropriately. The new mediator of this communication between tanycytes and neurons are the astrocytes. It is hoped that this finding can be beneficial to studies of obesity and eating disorders.