The sense of satiety induces man not to eat continuously and puts a brake on his need, often excessive, of food. Hunger and satiety affect everyone's eating behavior, but what exactly do they depend on?
Satiety is a signal triggered by the brain when it receives too much sugar. In fact, after a meal, when glucose levels momentarily rise, the signal reaches our brain, more precisely to astrocytes, the cells needed to support neurons. The astrocytes, at this point, they change shape and retract by activating some specific neurons of the hypothalamus, a structure of the central nervous system located in the central area of the two cerebral hemispheres, which in turn will send other signals to promote the feeling of satiety and tell us “hey you, you're bursting ".
Conversely, ghrelin is produced when we have an empty stomach, that is a hormone that in turn sends signals to our brain which is activated in search of food!
Fundamental studies conducted on rodents have clearly highlighted synaptic plasticity in the neuronal circuits that control appetite and metabolism, that is, the ability of neurons to modify their connections, adapt and create new circuits. In addition, some mice were also subjected to a diet rich in fat to make a comparison and it was seen that this type of diet does not have the same effect, that is, there is no remodeling of the astrocytes and no neurons are activated .
It could therefore be a lighter diet, or low in fat, promote synaptic plasticity?
This research appears to show that astrocytes change in the presence of glycemic changes, but further studies are still needed to confirm this. Al momento possiamo ipotizzare che l’alterazione di questo meccanismo regolatorio potrebbe essere alla base dei disordini alimentari e dell’obesità.