Dietary trans-10,cis-12 conjugated linoleic acid induces hyperinsulinemia and fatty liver in the mouse

Abstract : Conjugated linoleic acids (CLA) are a class of positional, geometric, conjugated dienoic isomers of linoleic acid (LA). Dietary CLA supplementation results in a dramatic decrease in body fat mass in mice, but also causes considerable liver steatosis. However, little is known of the molecular mechanisms leading to hepatomegaly. Although c9,t11- and t10,c12-CLA isomers are found in similar proportions in commercial preparations, the respective roles of these two molecules in liver enlargement has not been studied. We show here that mice fed a diet enriched in t10,c12-CLA (0.4% w/w) for 4 weeks developed lipoatrophy, hyperinsulinemia, and fatty liver, whereas diets enriched in c9,t11-CLA and LA had no significant effect. In the liver, dietary t10,c12-CLA triggered the ectopic production of peroxisome proliferator-activated receptor γ (PPARγ), adipocyte lipid-binding protein and fatty acid transporter mRNAs and induced expression of the sterol responsive element-binding protein-1a and fatty acid synthase genes. In vitro transactivation assays demonstrated that t10,c12- and c9,t11-CLA were equally efficient at activating PPARα, β/δ, and γ and inhibiting liver-X-receptor. Thus, the specific effect of t10,c12-CLA is unlikely to result from direct interaction with these nuclear receptors. Instead, t10,c12-CLA-induced hyperinsulinemia may trigger liver steatosis, by inducing both fatty acid uptake and lipogenesis.
Document type :
Journal articles
Complete list of metadatas

https://hal-agrosup-dijon.archives-ouvertes.fr/hal-01917166
Contributor : Administrateur Agrosupdijon <>
Submitted on : Friday, November 9, 2018 - 10:53:27 AM
Last modification on : Thursday, March 14, 2019 - 3:08:01 PM

Links full text

Identifiers

Citation

Lionel Clémént, Hélène Poirier, Isabelle Niot, Virginie Bocher, Michèle Guerre-Millo, et al.. Dietary trans-10,cis-12 conjugated linoleic acid induces hyperinsulinemia and fatty liver in the mouse. Journal of Lipid Research, American Society for Biochemistry and Molecular Biology, 2002, 43 (9), pp.1400 - 1409. ⟨10.1194/jlr.M20008-JLR200⟩. ⟨hal-01917166⟩

Share

Metrics

Record views

14