The effects of olive leaf extract from a Sicilian cultivar in an experimental model of hepatic steatosis

Olive oil is a well-known product for its health benefit, but the leaf has also been used as a traditional medicine in the Mediterranean for centuries. Olive leaves contain a great variety of chemical substances belonging to phenolic acids, phenolic alcohols, flavonoids and secoiridoids, and many other pharmacological active compounds with an important antioxidant effects such as oleuropein (OE), hydroxytyrosol (HT), tyrosol, cumaric acid, ferulic acid, caffeic acid, vanillic acid, rutin, verbascoside, luteolin, quercetin, dimethyloleuropein and ligstroside. Characterization of these compounds demonstrated that they can play an important role in human health, because of their ability to improve glucose homeostasis, ameliorate dyslipidemia and reduce inflammatory cytokine. The aim of this study was to investigate the effect of olive leaf extract (OLE) from Sicilian cultivar in an in vitro model of hepatic steatosis to evaluate the protective effects again free fatty acids accumulation in hepatocytes. We report here that OLE treatment ameliorated the lipid metabolism, and this effect was coupled with a parallel decrease in number of lipid droplets and a concomitant increase in FABP-4, SIRT-1 and HO-1 expression. Furthermore, OLE treatment induced a significantly reduction of the inflammatory cytokines IL-1β and TNF-α.