Natural Tocopherols in a Dietary Supplement of Lutein Affect Tissue Distribution of Tocopherols in Young Rats

Abstract

The effects of graded levels of Flora GLO (FG), a dietary supplement containing lutein derived from marigold flowers, on tissue concentrations of lutein and α- and γ-tocopherol were determined. Six groups of male weanling Fischer 344 rats (15/group) were fed ad libitum modified AIN-93G diets containing 0%, 0.30%, 0.60%, 1.20%, 2.40%, or 4.80% FG for eight weeks. FG provided 0%, 0.015%, 0.030%, 0.060%, 0.120%, or 0.240% lutein; corresponding levels of tocopherols were ~0%, 0.006%, 0.012%, 0.023%, 0.046%, and 0.092%, respectively. Maximal uptakes of lutein in plasma, spleen, and liver were observed with 4.8% FG. Lutein was not detectable in brain, heart, lung, testes, and kidney. Concentrations of αtocopherol in the plasma (μg/mg triglycerides) were reduced in all rats fed FG (p < 0.05). αTocopherol increased nonlinearly in lung, heart, and spleen with increased FG level. αTocopherol in liver increased with increased dietary FG; αtocopherol in kidney, testes, and brain did not increase. At each dietary level of FG, the spleen had a higher percentage of γtocopherol, and testes and brain had a lower percentage of γtocopherol than all other tissues. For all tissues, the concentrations of αtocopherol were always higher than those of γtocopherol. Tocopherols added to the dietary supplement for functional purposes appeared to have a significant effect on tissue levels of tocopherols. Therefore, changes in α and γtocopherol levels in tissues of rats fed FG cannot be attributed solely to effects of lutein.