Citrus peel inhibits oxidative stress in hyperlipidemic rats. Rats were placed on either an NCD or 60% HFD for eight weeks and were supplemented with ultra-pure water, metformin (100 mg/kg) or one of the indicated concentrations of citrus peel (50 and 100 mg/kg). In liver tissues, DHE was stained and the fluorescence images were required (A) and the fluorescence intensity for superoxide levels was quantified in liver (B). In liver lysates, MDA was analyzed (C) and in liver section, 4-HNE was stained as described in Materials and Methods (D). Values are mean ± SEM. (n = 7~8, * P < 0.05 vs. NCD-group, #
P < 0.05 vs. HFD-group). CPEW, citrus peel extract hot-air dry; CPEF, citrus peel extract freeze-drying; HFD, high-fat diet; NCD, normal calorie diet. Scale bars, 50 μm.