High fat diets modulate nitric oxide biosynthesis and antioxidant defence in red blood cells from C57BL/6 mice

The consumption of a high fat (HF) diet is considered a risk factor for the development of obesity. On the other hand, a monounsaturated HF diet has beneficial cardiometabolic effects. Since nitric oxide (NO) modulates vascular homeostasis, we investigate whether HF diets that vary in fatty acid composition have a different effect on the l-arginine-NO pathway and oxidative stress in C57BL/6 mice red blood cells (RBC). The olive oil diet induced an activation of l-arginine transport compared to other diets. NO synthase (NOS) activity was increased in all unsaturated HF diets (olive, sunflower and canola oils). Moreover, the expression of endothelial NOS (eNOS) and inducible NOS (iNOS) was increased in the olive oil group. In contrast, NOS activity from the lard group was decreased associated with diminished l-arginine transport. Olive oil also induced superoxide dismutase activation. Inhibition of the l-arginine-NO pathway in the lard group could contribute to cardiovascular diseases, while unsaturated HF diets may have a protector effect via enhanced NO bioavailability.