title: Leptin signaling is required for leucine deprivation-enhanced energy expenditure.
abstract: Leptin signaling in the hypothalamus is crucial in energy homeostasis. We have previously shown that dietary deprivation of the essential amino acid leucine in mice stimulates fat loss by increasing energy expenditure. The involvement of leptin signaling in this regulation, however, has not been reported. Here, we show that leucine deprivation promotes leptin signaling in mice maintained on an otherwise normal diet and restores leptin responses in mice maintained on a high fat diet, a regimen known to induce leptin resistance. In addition, we found that leucine deprivation stimulated energy expenditure, and fat loss was largely blocked in db/db mice homozygous for a mutation in leptin receptor and a knock-in mouse line Y3F with abrogation of leptin receptor Tyr(1138)-mediated signal transducer and activator transcript 3 signaling. Overall, our studies describe a novel link between hypothalamic leptin signaling and stimulation of energy expenditure under leucine deprivation.
authors.affiliation: From the Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Graduate School of the Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Zhang
authors.forename: Bin
authors.initials: B
authors.lastname: Liu
authors.forename: Ying
authors.initials: Y
authors.lastname: Cheng
authors.forename: Qingshu
authors.initials: Q
authors.lastname: Meng
authors.forename: Tingting
authors.initials: T
authors.lastname: Xia
authors.forename: Lei
authors.initials: L
authors.lastname: Jiang
authors.forename: Shanghai
authors.initials: S
authors.lastname: Chen
authors.forename: Yong
authors.initials: Y
authors.lastname: Liu
authors.forename: Feifan
authors.initials: F
authors.lastname: Guo
mesh_terms: D000818:Animals; D004041:Dietary Fats / Q000494:pharmacology; D004734:Energy Metabolism; D007031:Hypothalamus / Q000378:metabolism*; D020738:Leptin / Q000235:genetics / Q000378:metabolism*; D007930:Leucine / Q000172:deficiency*; D051379:Mice; D008817:Mice, Mutant Strains; D009154:Mutation; D054411:Receptors, Leptin / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction
chemical_list: D004041:Dietary Fats; D020738:Leptin; D054411:Receptors, Leptin; C515447:leptin receptor, mouse; D007930:Leucine
keywords: Energy Metabolism; Fat Loss; Hypothalamus; Leptin; Leucine Deprivation; STAT3; Uncoupling Proteins