High dietary oleic acid in olive oil-supplemented diet enhanced omega-3 fatty acid in blood plasma of rats

This study was conducted to investigate the effect of dietary oleic acid in olive oil-supplemented diets on the blood lipid profile and fatty acid composition in blood plasma and adipose tissue of rats. A total of 60 Sprague Dawley rats with mean body weight of 249 g +/- 3.04 g were equally divided into three diet groups: control (CON) contained 10% coconut oil, olive50 contained 5% coconut oil and 5% olive oil, and olive100 contained 10% olive oil. Oleic acid (OA) level was highest in olive100 followed by the olive50 and control. The final body weight (BW) of the rats was significantly affected by the intake of OA, in which rats fed olive100 had the lowest final BW, which signified that OA could be associated with weight loss. Olive oil intake significantly increased levels of the high-density lipoprotein cholesterol (HDL-C) and exhibited a potential attenuation effect on the glutamic-oxaloacetic transaminase and the glutamic-pyruvic transaminase, and a potential role in the reduction of triglycerides in the bloodstream of the animals. In terms of fatty acid composition, significantly high OA was observed in the blood plasma and adipose tissues of rats fed olive100. Omega-3 polyunsaturated fatty acids (PUFAs), such as linolenic (C18:3 n-3), eicosapentaenoic (C20:5 n-3), and docosahexaenoic (C22:6 n-3), and n-6 PUFA arachidonic (C20:4 n-6) were also significantly increased in the blood plasma of rats fed olive100. These findings suggest that the intake of dietary high OA may enhance the omega-3 fatty acid levels in the blood plasma of rats and may have a positive effect in reducing risks to cardiovascular disease, as evidenced by weight loss, increased HDL-C levels, and decreased TG levels in the blood plasma of experimental animals.