title: Gpr17 in AgRP Neurons Regulates Feeding and Sensitivity to Insulin and Leptin.
abstract: Hypothalamic neurons expressing agouti-related peptide (AgRP) regulate eating and glucose metabolism. Ablation of FOXO1 in AgRP neurons of mice results in reduced food intake, leanness, improved glucose homeostasis, and increased sensitivity to insulin and leptin. We tentatively identified G-protein-coupled receptor Gpr17 as an effector of FOXO1 orexigenic signals in AgRP neurons. In this study, we generated and characterized AgRP neuron-specific Gpr17 knockout mice (Agrp-Gpr17(-/-)) to test the hypothesis that Gpr17 regulates appetite, energy expenditure, and metabolism. Agrp-Gpr17(-/-) mice show reduced food intake, increased relative energy expenditure, and increased satiety, resulting in leanness and reduced body fat. They also show increased central nervous system sensitivity to insulin and leptin and reduced plasma glucose excursions following the administration of glucose or pyruvate. In summary, AgRP neuron-specific Gpr17 knockouts phenocopy FOXO1 knockouts in the same cell type, thus supporting our original hypothesis and providing further impetus to develop Gpr17 antagonists for the treatment of obesity.
authors.affiliation: Naomi Berrie Diabetes Center and Department of Medicine, Columbia University Medical Center, New York, NY hr2255@cumc.columbia.edu da230@cumc.columbia.edu.
authors.forename: Hongxia
authors.initials: H
authors.lastname: Ren
authors.affiliation: Naomi Berrie Diabetes Center and Department of Medicine, Columbia University Medical Center, New York, NY.
authors.forename: Joshua R
authors.initials: JR
authors.lastname: Cook
authors.affiliation: Institute for Cancer Genetics, Columbia University Medical Center, New York, NY.
authors.forename: Ning
authors.initials: N
authors.lastname: Kon
authors.affiliation: Naomi Berrie Diabetes Center and Department of Medicine, Columbia University Medical Center, New York, NY hr2255@cumc.columbia.edu da230@cumc.columbia.edu.
authors.forename: Domenico
authors.initials: D
authors.lastname: Accili
mesh_terms: D054369:Agouti-Related Protein / Q000378:metabolism*; D000818:Animals; D001823:Body Composition / Q000502:physiology; D004435:Eating / Q000502:physiology*; D004734:Energy Metabolism / Q000502:physiology; D007031:Hypothalamus / Q000378:metabolism*; D007333:Insulin Resistance / Q000502:physiology*; D020738:Leptin / Q000378:metabolism*; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D009474:Neurons / Q000378:metabolism*; D043562:Receptors, G-Protein-Coupled / Q000235:genetics / Q000378:metabolism*
chemical_list: D054369:Agouti-Related Protein; C534979:GPR17 protein, mouse; D020738:Leptin; D009419:Nerve Tissue Proteins; D043562:Receptors, G-Protein-Coupled