The Role of Gut Glucose Metabolism in the Control of Food Intake

Glucose homeostasis is a crucial physiological function of the living organisms. A system of plasma glucose sensing present in the portal vein plays a key role in this homeostasis. Connected to the hypothalamus via the peripheral nervous system, it allows the body to adapt its response to any variation in portal glycemia. The hypothalamus notably controls food intake. Intestinal gluconeogenesis, via the release of glucose into the portal vein, plays a key role in the control of hunger and satiety. The induction of intestinal gluconeogenesis has provided a physiological explanation to the satiety effects induced by protein-enriched diets. Intestinal gluconeogenesis has also provided an explanation to the early curbing of hunger and improvement in glucose control observed in obese diabetic patients treated by gastric bypass surgery. These data have emphasized the importance of the gut gluconeogenesis to brain axis in the control of the sensations of hunger and satiety and in glucose homeostasis. Keywords: Portal glucose signal, intestinal gluconeogenesis, Glycolysis, insulin sensitivity, hypothalamus, glycemia, energy homeostasis, hepatoportal vagal, spinal afferents, gluconeogenesis