The mere sight of a meal triggers an inflammatory response in the brain
Even before carbohydrates reach the bloodstream, the very sight and smell of a meal trigger the release of insulin. For the first time, researchers from the University of Basel and University Hospital Basel have shown that this insulin release depends on a short-term inflammatory response that takes place in these circumstances. In overweight individuals, however, this inflammatory response is so excessive that it can impair insulin secretion.
Even the anticipation of a forthcoming meal triggers a series of responses in the body, perhaps the most familiar of which is the watering of the mouth. But the hormone insulin, which regulates blood sugar, also arrives on the scene even before we tuck into the first mouthful of food. Experts refer to this as the neurally mediated (or cephalic) phase of insulin secretion.
Meal stimulates immune defense
In the past, however, it was unclear how the sensory perception of a meal generated a signal to the pancreas to ramp up insulin production. Now, researchers from the University of Basel and University Hospital Basel have identified an important piece of the puzzle: an inflammatory factor known as interleukin 1 beta (IL1B), which is also involved in the immune response to pathogens or in tissue damage. The team have reported their findings in the journal Cell Metabolism.
“The fact that this inflammatory factor is responsible for a considerable proportion of normal insulin secretion in healthy individuals is surprising, because it’s also involved in the development of type 2 diabetes,” explains study leader Professor Marc Donath from the Department of Biomedicine and the Department of Endocrinology.