title: Glucose and hypothalamic astrocytes: More than a fueling role?
abstract: Brain plays a central role in energy homeostasis continuously integrating numerous peripheral signals such as circulating nutrients, and in particular blood glucose level, a variable that must be highly regulated. Then, the brain orchestrates adaptive responses to modulate food intake and peripheral organs activity in order to achieve the fine tuning of glycemia. More than fifty years ago, the presence of glucose-sensitive neurons was discovered in the hypothalamus, but what makes them specific and identifiable still remains disconnected from their electrophysiological signature. On the other hand, astrocytes represent the major class of macroglial cells and are now recognized to support an increasing number of neuronal functions. One of these functions consists in the regulation of energy homeostasis through neuronal fueling and nutrient sensing. Twenty years ago, we discovered that the glucose transporter GLUT2, the canonical "glucosensor" of the pancreatic beta-cell together with the glucokinase, was also present in astrocytes and participated in hypothalamic glucose sensing. Since then, many studies have identified other actors and emphasized the astroglial participation in this mechanism. Growing evidence suggest that astrocytes form a complex network and have to be considered as spatially coordinated and regulated metabolic units. In this review we aim to provide an updated view of the molecular and respective cellular pathways involved in hypothalamic glucose sensing, and their relevance in physiological and pathological states.
authors.affiliation: Centre des Sciences du Goût de l'Alimentation, CNRS UMR 6265, Dijon, France; Centre des Sciences du Goût de l'Alimentation, INRA UMR 1324, Dijon, France; Centre des Sciences du Goût de l'Alimentation, Université de Bourgogne, Dijon, France. Electronic address: corinne.leloup@u-bourgogne.fr.
authors.forename: C
authors.initials: C
authors.lastname: Leloup
authors.affiliation: Centre des Sciences du Goût de l'Alimentation, CNRS UMR 6265, Dijon, France; Centre des Sciences du Goût de l'Alimentation, INRA UMR 1324, Dijon, France; Centre des Sciences du Goût de l'Alimentation, Université de Bourgogne, Dijon, France. Electronic address: callard@tulane.edu.
authors.forename: C
authors.initials: C
authors.lastname: Allard
authors.affiliation: Centre des Sciences du Goût de l'Alimentation, CNRS UMR 6265, Dijon, France; Centre des Sciences du Goût de l'Alimentation, INRA UMR 1324, Dijon, France; Centre des Sciences du Goût de l'Alimentation, Université de Bourgogne, Dijon, France. Electronic address: lionel.carneiro@unil.ch.
authors.forename: L
authors.initials: L
authors.lastname: Carneiro
authors.affiliation: Centre des Sciences du Goût de l'Alimentation, CNRS UMR 6265, Dijon, France; Centre des Sciences du Goût de l'Alimentation, INRA UMR 1324, Dijon, France; Centre des Sciences du Goût de l'Alimentation, Université de Bourgogne, Dijon, France. Electronic address: xavier.fioramonti@dijon.inra.fr.
authors.forename: X
authors.initials: X
authors.lastname: Fioramonti
authors.affiliation: Centre des Sciences du Goût de l'Alimentation, CNRS UMR 6265, Dijon, France; Centre des Sciences du Goût de l'Alimentation, INRA UMR 1324, Dijon, France; Centre des Sciences du Goût de l'Alimentation, Université de Bourgogne, Dijon, France. Electronic address: stephan.collins@u-bourgogne.fr.
authors.forename: S
authors.initials: S
authors.lastname: Collins
authors.affiliation: Centre des Sciences du Goût de l'Alimentation, CNRS UMR 6265, Dijon, France; Centre des Sciences du Goût de l'Alimentation, INRA UMR 1324, Dijon, France; Centre des Sciences du Goût de l'Alimentation, Université de Bourgogne, Dijon, France. Electronic address: luc.penicaud@u-bourgogne.fr.
authors.forename: L
authors.initials: L
authors.lastname: Pénicaud
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000378:metabolism*; D017629:Gap Junctions / Q000378:metabolism; D005947:Glucose / Q000378:metabolism*; D006801:Humans; D007031:Hypothalamus / Q000378:metabolism*
chemical_list: D005947:Glucose
keywords: astroglial gap junctions; astroglial hemichannels; connexins 30 and 43; glucose; hypothalamic glucose sensing; lactate