title: Central exercise action increases the AMPK and mTOR response to leptin.
abstract: AMP-activated protein kinase (AMPK) and mammalian Target of Rapamycin (mTOR) are key regulators of cellular energy balance and of the effects of leptin on food intake. Acute exercise is associated with increased sensitivity to the effects of leptin on food intake in an IL-6-dependent manner. To determine whether exercise ameliorates the AMPK and mTOR response to leptin in the hypothalamus in an IL-6-dependent manner, rats performed two 3-h exercise bouts, separated by one 45-min rest period. Intracerebroventricular IL-6 infusion reduced food intake and pretreatment with AMPK activators and mTOR inhibitor prevented IL-6-induced anorexia. Activators of AMPK and fasting increased food intake in control rats to a greater extent than that observed in exercised ones, whereas inhibitor of AMPK had the opposite effect. Furthermore, the reduction of AMPK and ACC phosphorylation and increase in phosphorylation of proteins involved in mTOR signal transduction, observed in the hypothalamus after leptin infusion, were more pronounced in both lean and diet-induced obesity rats after acute exercise. Treatment with leptin reduced food intake in exercised rats that were pretreated with vehicle, although no increase in responsiveness to leptin-induced anorexia after pretreatment with anti-IL6 antibody, AICAR or Rapamycin was detected. Thus, the effects of leptin on the AMPK/mTOR pathway, potentiated by acute exercise, may contribute to appetite suppressive actions in the hypothalamus.
authors.affiliation: Department of Internal Medicine, FCM, State University of Campinas (UNICAMP), Campinas, São Paulo, Brazil.
authors.forename: Eduardo R
authors.initials: ER
authors.lastname: Ropelle
authors.forename: Maria Fernanda A
authors.initials: MF
authors.lastname: Fernandes
authors.forename: Marcelo B S
authors.initials: MB
authors.lastname: Flores
authors.forename: Mirian
authors.initials: M
authors.lastname: Ueno
authors.forename: Silvana
authors.initials: S
authors.lastname: Rocco
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Marin
authors.forename: Dennys E
authors.initials: DE
authors.lastname: Cintra
authors.forename: Lício A
authors.initials: LA
authors.lastname: Velloso
authors.forename: Kleber G
authors.initials: KG
authors.lastname: Franchini
authors.forename: Mario J A
authors.initials: MJ
authors.lastname: Saad
authors.forename: José B C
authors.initials: JB
authors.lastname: Carvalheira
mesh_terms: D055372:AMP-Activated Protein Kinases / Q000378:metabolism*; D000818:Animals; D004435:Eating / Q000502:physiology; D007031:Hypothalamus / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D020738:Leptin / Q000378:metabolism*; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D010766:Phosphorylation; D010805:Physical Conditioning, Animal; D011494:Protein Kinases / Q000378:metabolism*; D051381:Rats; D015398:Signal Transduction; D058570:TOR Serine-Threonine Kinases
chemical_list: D055372:AMP-Activated Protein Kinases; D015850:Interleukin-6; D020738:Leptin; D019869:Phosphatidylinositol 3-Kinases; D011494:Protein Kinases; D058570:TOR Serine-Threonine Kinases