Extra virgin olive oil improved body weight and insulin sensitivity in high fat diet-induced obese LDLr−/−.Leiden mice without attenuation of steatohepatitis
Dietary fatty acids play a role in the pathogenesis of obesity-associated non-alcoholic fatty liver
disease (NAFLD), which is associated with insulin resistance (IR). Fatty acid composition is critical
for IR and subsequent NAFLD development. Extra-virgin olive oil (EVOO) is the main source of
monounsaturated fatty acids (MUFA) in Mediterranean diets. This study examined whether EVOO containing high fat diets may prevent diet-induced NAFLD using Ldlr−/−. Leiden mice. In female
Ldlr−/−.Leiden mice, the efects of the following high fat diets (HFDs) were examined: a lard-based
HFD (HFD-L); an EVOO-based HFD (HFD-EVOO); a phenolic compounds-rich EVOO HFD (HFD-OL).
We studied changes in body weight (BW), lipid profle, transaminases, glucose homeostasis, liver
pathology and transcriptome. Both EVOO diets reduced body weight (BW) and improved insulin
sensitivity. The EVOOs did not improve transaminase values and increased LDL-cholesterol and liver
collagen content. EVOOs and HFD-L groups had comparable liver steatosis. The profbrotic efects
were substantiated by an up-regulation of gene transcripts related to glutathione metabolism,
chemokine signaling and NF-kappa-B activation and down-regulation of genes relevant for fatty acid
metabolism. Collectivelly, EVOO intake improved weight gain and insulin sensitivity but not liver
infammation and fbrosis, which was supported by changes in hepatic genes expression