Hypolipidemic Effect of Blended Oil in Hamster: Biochemical Analysis and Gene Expression Profiling

Edible oils form an essential part of the modern diet. Cardiovascular disease (CVD) has become one of the leading causes of death worldwide. Dietary supplementation with certain edible oils may play a vital role in improving cardiovascular health and reducing the mortality rate due to heart disease. Palm oil (PO), sunflower oil (SFO), soybean oil (SBO) and blended oils (consisting of olive oil (OLO) with SFO or SBO), were prepared (65-69% MUFA) to provide higher amounts of MUFA. Animal experiments were carried out to find the effects of olive oil blends, by feeding hamsters diets containing 8% of either native or blends of oils for 60 days. Serum cholesterol levels were reduced by 27% and 29%, respectively, in hamsters given blended oils containing OLO/SFO and OLO/SBO compared to PO. Fecal cholesterol and thiobarbituric acid did not show a significant change when hamsters were given blends in comparison with PO. Body and liver weights were also not significantly affected. These studies indicated that the atherogenic potentials of PUFA-rich SFO and SBO can be significantly decreased by blending with an oil rich in MUFA, such as OLO, in appropriate amounts. These results illustrate that blended oil significantly affects the gene expression of lipoprotein and fatty acid transporter in hamster hepatocytes. Dietary blended oil up-regulated the mRNA levels of lipin, while it down-regulated lipoprotein and cytochrome P450s. The effects of blended oil on the aforementioned genes, except lipoprotein, could be extrapolated towards decreased LDL oxidation. These findings suggest that dietary blended oil and PO alter the expression of different genes associated with contact of lipoprotein in liver.