title: Microarray analysis of hepatic genes differentially expressed in the presence of the unsaponifiable fraction of olive oil in apolipoprotein E-deficient mice.
abstract: The hypothesis that the unsaponifiable fraction of olive oil dramatically influences hepatic gene expression was tested in mice. Two olive oils, obtained from the same olive cultivar but by different technological procedures, were characterized to show that they differed mainly in terms of the composition/quantity of this unsaponifiable fraction. Using DNA microarrays, hepatic gene expression was analysed in apoE-deficient mice fed one of two isoenergetic, isonitrogenous diets containing either 10 % (w/w) olive oil or unsaponifiable fraction-enriched olive oil. To provide an initial screening of potential candidate genes involved in a differential response, only genes with remarkably modified expression (signal log2 ratio >3 or < - 3) were further considered. The eleven genes fulfilling these prerequisites were confirmed by quantitative RT-PCR, and then analysed in apoE-deficient mice with a C57BL/6J genetic background. Orosomucoid and serum amyloid A2 were upregulated (to variable extents depending on the genetic background) in the absence of hepatic steatosis and inflammation. Fabp5 and Mt2 were also strongly upregulated. Several proteases were highly suppressed by the unsaponifiable-enriched olive diet, independent of the genetic background. The findings indicate that change in the expression of these genes is a good marker of the intake of the unsaponifiable fraction of olive oil. The results highlight the important biological effects of the unsaponifiable fraction of olive oil. The term 'monounsaturated fatty acid-enriched oil' no longer appears appropriate for describing all the oils to which it is currently applied since it does not adequately reflect that they have different biological effects.
authors.affiliation: Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Veterinaria, Instituto Aragonés de Ciencias de la Salud (Universidad de Zaragoza-Dirección Salud del Gobiemo de Aragón), Miguel Servet 177, E-50013 Zaragoza, Spain.
authors.forename: Sergio
authors.initials: S
authors.lastname: Acín
authors.forename: María A
authors.initials: MA
authors.lastname: Navarro
authors.forename: Javier S
authors.initials: JS
authors.lastname: Perona
authors.forename: Joaquín C
authors.initials: JC
authors.lastname: Surra
authors.forename: Natalia
authors.initials: N
authors.lastname: Guillen
authors.forename: Carmen
authors.initials: C
authors.lastname: Arnal
authors.forename: Alfonso J
authors.initials: AJ
authors.lastname: Sarría
authors.forename: José M
authors.initials: JM
authors.lastname: Arbonés-Mainar
authors.forename: Ricardo
authors.initials: R
authors.lastname: Carnicer
authors.forename: Valentina
authors.initials: V
authors.lastname: Ruiz-Gutiérrez
authors.forename: Jesús
authors.initials: J
authors.lastname: Osada
mesh_terms: D000818:Animals; D001057:Apolipoproteins E / Q000172:deficiency*; D004032:Diet; D004042:Dietary Fats, Unsaturated / Q000494:pharmacology*; D005227:Fatty Acids / Q000032:analysis; D005511:Food Handling / Q000379:methods; D005786:Gene Expression Regulation / Q000187:drug effects*; D008099:Liver / Q000378:metabolism*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D046228:Microarray Analysis; D000069463:Olive Oil; D010938:Plant Oils / Q000737:chemistry / Q000494:pharmacology*; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods
chemical_list: D001057:Apolipoproteins E; D004042:Dietary Fats, Unsaturated; D005227:Fatty Acids; D000069463:Olive Oil; D010938:Plant Oils; D012333:RNA, Messenger