Effects of Annurca apple polyphenols on lipid metabolism in HepG2 cell lines: A source of nutraceuticals potentially indicated for the metabolic syndrome

•Polyphenolic extracts from five apple cultivars were tested on HepG2 cells•Annurca flesh proved the best inhibition capacity against lipase activity•Annurca flesh was the most effective in enhancing LDL receptor binding activity•Annurca flesh led to the highest increase in HDL cell medium concentration

The influence of polyphenolic extracts from Annurca apple peel and flesh on lipid metabolism in human hepatocellular liver carcinoma (HepG2) cell lines was evaluated, and compared with those of other conventional cultivars, such as Red Delicious (RD), Pink Lady (PL), Fuji (F) and Golden Delicious (GD). Annurca flesh revealed the best inhibition capacity against lipase activity, and triglyceride levels in the cell medium increased by almost 20 times above control levels. Incubation with Annurca flesh polyphenols enhanced low-density lipoproteins (LDL) receptor binding activity by 40% and led to an increase in Apolipoprotein A1 (ApoA1) cell expression of 33.3% above control levels. Experimental data would indicate for Annurca flesh polyphenols a significant hypolipidemic potential in comparison with other more common apple cultivars, thus leading to hypothesise a helpful role in the prevention and care of diseases in subjects affected by metabolic syndrome and to propose the possibility of formulating therapeutically useful nutraceutical products. Undoubtedly, further in vivo and clinical studies are needed to confirm such healthy effects through diet.