title: High-lard and high-fish-oil diets differ in their effects on function and dynamic behaviour of rat hepatic mitochondria.
abstract: BACKGROUND
  Mitochondria are dynamic organelles that frequently undergo fission and fusion processes, and imbalances in these processes may be involved in obesity and insulin resistance.
  
  
  OBJECTIVE
  The present work had the following aims: (a) to evaluate whether the mitochondrial dysfunction present in the hepatic steatosis induced by a high-fat diet is associated with changes in mitochondrial dynamics and morphology; (b) to evaluate whether effects on the above parameters differ between high-lard and high-fish-oil diets, as it has been suggested that fish oil may have anti-obesity and anti-steatotic effects by stimulating fatty acids utilisation.
  
  
  METHODS
  The development of hepatic steatosis and insulin resistance was monitored in rats fed a high-lard or high-fish-oil diet. Immunohistochemical and electronic microscopic observations were performed on liver sections. In isolated liver mitochondria, assessments of fatty acids oxidation rate, proton conductance and oxidative stress (by measuring H2O2 release and aconitase activity) were performed. Western blot and immunohistochemical analyses were performed to evaluate the presence of proteins involved in mitochondrial dynamics (i.e., fusion and fission processes). To investigate the fusion process, mitofusin 2 and autosomal dominant optic atrophy-1 (OPA1) were analysed. To investigate the fission process, the presence of dynamin-related protein 1 (Drp1) and fission 1 protein (Fis1) was assessed.
  
  
  RESULTS
  High-lard feeding elicited greater hepatic lipid accumulation, insulin resistance with associated mitochondrial dysfunction, greater oxidative stress and a shift towards mitochondrial fission processes (versus high-fish-oil feeding, which had an anti-steatotic effect associated with increased mitochondrial fusion processes).
  
  
  CONCLUSIONS
  Different types of high-fat diets differ in their effect on mitochondrial function and dynamic behaviour, leading to different cellular adaptations to over-feeding.
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: Maria Pina
authors.initials: MP
authors.lastname: Mollica
authors.affiliation: Department of Biology, University of Naples "Federico II", Naples, Italy.
authors.forename: Immacolata
authors.initials: I
authors.lastname: Donizzetti
authors.affiliation: Department of Biology, University of Naples "Federico II", Naples, Italy.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Gifuni
authors.affiliation: Department of Biology, University of Naples "Federico II", Naples, Italy.
authors.forename: Raffaella
authors.initials: R
authors.lastname: Sica
authors.affiliation: Department of Biology, University of Naples "Federico II", Naples, Italy.
authors.forename: Angelica
authors.initials: A
authors.lastname: Pignalosa
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: Marcello
authors.initials: M
authors.lastname: Gaita
authors.affiliation: Department of Biology, University of Naples "Federico II", Naples, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: De Filippo
authors.affiliation: Departament de Bioquímica i Biologia Molecular, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Zorzano
authors.affiliation: Department of Biology, University of Naples "Federico II", Naples, Italy.
authors.forename: Rosalba
authors.initials: R
authors.lastname: Putti
mesh_terms: D000818:Animals; D004041:Dietary Fats / Q000494:pharmacology*; D005395:Fish Oils / Q000494:pharmacology*; D050356:Lipid Metabolism / Q000187:drug effects*; D008297:Male; D008930:Mitochondria, Liver / Q000378:metabolism* / Q000648:ultrastructure; D063154:Mitochondrial Dynamics / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D004041:Dietary Fats; D005395:Fish Oils; C029310:lard