title: Metabolic effects of portal vein sensing.
abstract: The extrinsic gastrointestinal nerves are crucial in the sensing of nutrients and hormones and its translation in terms of control of food intake. Major macronutrients like glucose and protein are sensed by the extrinsic nerves located in the portal vein walls, which signal to the brain and account for the satiety phenomenon they promote. Glucose is sensed in the portal vein by neurons expressing the glucose receptor SGLT3, which activate the main regions of the brain involved in the control of food intake. Proteins indirectly act on food intake by inducing intestinal gluconeogenesis and its sensing by the portal glucose sensor. The mechanism involves a prior antagonism by peptides of the μ-opioid receptors present in the portal vein nervous system and a reflex arc with the brain inducing intestinal gluconeogenesis. In a comparable manner, short-chain fatty acids produced from soluble fibre act via intestinal gluconeogenesis to exert anti-obesity and anti-diabetic effects. In the case of propionate, the mechanism involves a prior activation of the free fatty acid receptor FFAR3 present in the portal nerves and a reflex arc initiating intestinal gluconeogenesis.
authors.affiliation: Inserm U855, Faculté de Médecine Lyon-Est Laennec, Lyon, France; Faculté de Médecine Lyon-Est Laennec, Université Lyon 1, Villeurbanne, France; Faculté de Médecine Lyon-Est Laennec, Université de Lyon, Lyon, France.
authors.forename: G
authors.initials: G
authors.lastname: Mithieux
mesh_terms: D000818:Animals; D001069:Appetite Regulation; D001786:Blood Glucose / Q000378:metabolism*; D004043:Dietary Fiber / Q000378:metabolism; D004044:Dietary Proteins / Q000378:metabolism; D019422:Dietary Sucrose / Q000378:metabolism; D025461:Feedback, Physiological; D005943:Gluconeogenesis; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism; D008954:Models, Biological; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009475:Neurons, Afferent / Q000166:cytology / Q000378:metabolism*; D011169:Portal Vein / Q000294:innervation / Q000378:metabolism*; D012528:Satiety Response; D051247:Sodium-Glucose Transport Proteins / Q000378:metabolism*; D015854:Up-Regulation
chemical_list: D001786:Blood Glucose; D004043:Dietary Fiber; D004044:Dietary Proteins; D019422:Dietary Sucrose; D009419:Nerve Tissue Proteins; C490298:SLC5A4 protein, human; D051247:Sodium-Glucose Transport Proteins
keywords: diabetes; gastrointestinal neural system; gluconeogenesis; intestine; obesity; portal vein; protein-enriched diet; soluble fibre