Antioxidant and anti‐inflammatory effects of lutein in aorta and liver of guinea pigs fed with a hypercholesterolemic diet.

Abstract

The effects of the carotenoid, lutein on atherosclerosis and liver oxidation were tested in guinea pigs fed a hypercholesterolemic diet (0.25 g/100 g dietary cholesterol). Guinea pigs were divided into two groups, control group (n = 9) or Lutein group (n = 10) (0.1 g/100 g lutein) and fed the experimental diets for 12 wk. Hematoxylin and eosin (H&E) stained aorta was examined and aortic and liver malondialdehyde (MDA) concentrations were analyzed by TBARS assay. Plasma and aortic cytokine concentrations were measured by Immunoassay and liver enzymes, alkaline phosphatase (ALP) and alanine transaminase (ALT) were measured. Aortic MDA concentrations were lower in the Lutein (1.7 ± 1.3 nmol/mg protein) compared to the control group (3.0 ± 1.4 nmol/mg protein) (P < 0.05) and H&E staining indicated separation and disrupted morphology of aortas in control guinea pigs while these features were not shown in the Lutein group. Aortic MDA positively correlated with aortic cytokines. Plasma concentration of ALP and ALT were not different between groups, however, liver MDA concentrations were lower in the Lutein group (6.0 ± 1.0 nmol/mg protein) compared to the control group (7.0 ± 1.0 nmol/mg protein) (P < 0.05). Liver MDA concentrations were negatively correlated with liver lutein concentrations (r=−0.469, p<0.05). These results suggest protective antioxidant and anti‐inflammatory effects of lutein in both liver and aorta.