title: Effects of an High-Fat Diet Enriched in Lard or in Fish Oil on the Hypothalamic Amp-Activated Protein Kinase and Inflammatory Mediators.
abstract: The high fat diet (HFD) rich in lard induces obesity, inflammation and oxidative stress, and the deregulation of hypothalamic nuclei plays an important role in this mechanism. One important factor involved in the food intake and inflammation is adenosine monophosphate-dependent kinase (AMPK), a serine/threonine kinase activated by phosphorylation. Omega (ω)3-polyunsaturated fatty acids (PUFA) are dietary compounds known to attenuate the obesity-related diseases, although the molecular mechanisms underlying their actions in the hypothalamus are not completely understood. We hypothesized that the beneficial effects of PUFA may be mediated by AMPK in the hypothalamus. To this aim, rats were fed a control diet (CD), or isocaloric HFD containing either fish oil (FD; rich in ω3-PUFA) or lard for 6 weeks, and the activation of AMPK, inflammatory state (IKKβ, TNF-α) and oxidative stress were analyzed in the hypothalamus. In addition, we also studied serum lipid profile, homeostatic model assessment (HOMA) index, and pro-inflammatory parameters. Our results showed, at the hypothalamic level of LD-fed rats, an increase of AMPK activation, inflammation and oxidative stress, while no modifications were detected in FD-fed animals compared to CD. In addition body weight gain, serum lipid profile, pro-inflammatory parameters and insulin resistance were reduced in FD animals compared to LD. In conclusion, our data indicate that the substitution of saturated by unsaturated fatty acids in the diet has beneficial effects on modulation of hypothalamic inflammation and function in obesity, underlying, at hypothalamic level, the interaction among insulin and/or leptin resistance, AMPK activation and hyperphagia.
authors.affiliation: Department of Experimental Medicine-Section of Human Physiology, Second University of NaplesNaples, Italy; Department of Medicine, University of PadovaPadua, Italy.
authors.forename: Emanuela
authors.initials: E
authors.lastname: Viggiano
authors.affiliation: Department of Biology, University of Naples Federico II Naples, Italy.
authors.forename: Maria Pina
authors.initials: MP
authors.lastname: Mollica
authors.affiliation: Department of Biology, University of Naples Federico II Naples, Italy.
authors.forename: Lillà
authors.initials: L
authors.lastname: Lionetti
authors.affiliation: Department of Biology, University of Naples Federico II Naples, Italy.
authors.forename: Gina
authors.initials: G
authors.lastname: Cavaliere
authors.affiliation: Department of Biology, University of Naples Federico II Naples, Italy.
authors.forename: Giovanna
authors.initials: G
authors.lastname: Trinchese
authors.affiliation: Department of Biology, University of Naples Federico II Naples, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: De Filippo
authors.affiliation: Department of Experimental Medicine-Section of Human Physiology, Second University of Naples Naples, Italy.
authors.forename: Sergio
authors.initials: S
authors.lastname: Chieffi
authors.affiliation: Department of Biology, University of Naples Federico II Naples, Italy.
authors.forename: Marcello
authors.initials: M
authors.lastname: Gaita
authors.affiliation: Department of Biology, University of Naples Federico II Naples, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Barletta
authors.affiliation: Department of Experimental Medicine-Section of Human Physiology, Second University of Naples Naples, Italy.
authors.forename: Bruno
authors.initials: B
authors.lastname: De Luca
authors.affiliation: Department of Biology, University of Naples Federico II Naples, Italy.
authors.forename: Marianna
authors.initials: M
authors.lastname: Crispino
authors.affiliation: Department of Experimental Medicine-Section of Human Physiology, Second University of Naples Naples, Italy.
authors.forename: Marcellino
authors.initials: M
authors.lastname: Monda
keywords: AMPK; high fat diet; inflammation; oxidative stress; ω3-PUFA