Polyphenolic extract attenuates fatty acid-induced steatosis and oxidative stress in hepatic and endothelial cells
Phenolic compounds (PC) of virgin olive oil exert several biochemical and pharmacological beneficial effects. Some dietary PC seem to prevent/improve obesity and metabolic-related disorders such as non-alcoholic fatty liver disease (NAFLD). We investigated the possible effects of PC extracted from olive pomace (PEOP) and of the main single molecules present in the extract (tyrosol, apigenin, oleuropein, p-coumaric and caffeic acid) in protecting hepatocytes and endothelial cells against triglyceride accumulation and oxidative stress.
Rat hepatoma and human endothelial cells were exposed to a mixture of oleate/palmitate to mimic the condition of NAFLD and atherosclerosis, respectively. Then, cells were incubated for 24 h in the absence or in the presence of PC or PEOP. Different parameters were evaluated, such as lipid accumulation and oxidative stress-related markers.
In hepatic cells, expression of peroxisome proliferator-activated receptors (PPARs) and of stearoyl-CoA desaturase 1 (SCD-1) were assessed as index of lipid metabolism. In endothelial cells, expression of intercellular adhesion molecule-1 (ICAM-1), activation of nuclear factor kappa-B (NF-kB), release of nitric oxide (NO), and wound-healing rate were assessed as index of inflammation.
PEOP extract ameliorated hepatic lipid accumulation and lipid-dependent oxidative imbalance thus showing potential applications as therapeutic agent tuning down hepatosteatosis and atherosclerosis.
KeywordsNon-alcoholic fatty liver disease Atherosclerosis Olive pomace Phenolic compound Oxidative stress
This research was supported by grants from MIUR-COFIN (Prot. 20089SRS2X_002), Compagnia San Paolo Torino (Prat. No. 2009.1824-1067/IT/pv), University of Genova (no. 2015), European Joint Programming Initiative “A Healthy Diet for a Healthy Life (JPI HDHL)–National Project Wellness, Nutrition, Sport and Exercise prevention (WISE) 2013–16 (PP).
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
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