GLP-1 has a direct effect on hepatocytes, by activating genes involved in fatty acid β-oxidation and insulin sensitivity. GLP-1 analogues could be a promising treatment approach to improve hepatic insulin resistance in patients with NAFLD/NASH.

No abstract

Insulin resistance induces nonalcoholic fatty liver disease and nonalcoholic steatohepatitis (NASH). We used a high-fat, high-calorie solid diet (HFD) to create a model of insulin resistance and NASH in nongenetically modified rats and to study the relationship between visceral adipose tissue and liver. Obesity and insulin resistance occurred in HFD rats, accompanied by a progressive increase in visceral adipose tissue tumor necrosis factor (TNF)-␣ mRNA and in circulating free fatty acids. HFD also decreased adiponectin mRNA and peroxisome proliferator-activated receptor (PPAR)-␣ expression in the visceral adipose tissue and the liver, respectively, and induced hepatic insulin resistance through TNF-␣-mediated c-Jun N-terminal kinase (JNK)-dependent insulin receptor substrate-1 Ser307 phosphorylation. These modifications lead to hepatic steatosis accompanied by oxidative stress phenomena, necroinflammation, and hepatocyte apoptosis at 4 weeks and by pericentral fibrosis at 6 months. Supplementation of n-3 polyunsaturated fatty acid, a PPAR␣ ligand, to HFD-treated animals restored hepatic adiponectin and PPAR␣ expression, reduced TNF-␣ hepatic levels, and ameliorated fatty liver and the degree of liver injury. Thus, our model mimics the most common features of NASH in humans and provides an ideal tool to study the role of individual pathogenetic events (as for PPAR␣ downregulation) and to define any future experimental therapy, such as n-3 polyunsaturated fatty acid, which ameliorated the degree of liver injury. (Am J

No abstract

Interspecific hybrid Elaeis oleifera × E. guineensis (O×G) palm is currently receiving increasing attention because of its interesting glycerides structure and composition. In this study, the alcoholic constituents of unsaponifiable matter of crude hybrid O×G palm oil were characterized for the first time and compared to data obtained analyzing crude African palm oil (E. guineensis).Total unsaponifiable matter content was 1.18 ± 0.11 g/100 g in O×G hybrid oil and 1.05 ± 0.06 g/100 g in African palm oil. O×G oil was characterized by lower contents of squalene and alcoholic constituents where the main differences concerned 4‐desmethylsterols and isoprenoid alcohols: O×G oil was characterized by higher (23.6 ± 6.1 %) contents of isoprenoid alcohols and by a different phytol/geranylgeraniol ratio. The tocol fraction constituted the class of unsaponifiable components on which the genetic exerts the greatest influence: tocol content showed no significant differences between the two oils, however, hybrid palm oil was characterized by higher percentages of γ‐tocotrienol (59.7 ± 1.1) and δ‐tocotrienol (11.7 ± 0.8) and lower percentages of tocopherols (10.6 ± 0.3), almost entirely constituted of the α isomer. These results suggest that O×G oil can also be considered an interesting alimentary source of nutraceutical components, especially for bioactive tocotrienols.