Dietary lutein from marigold extract inhibits mammary tumor development in BALB/c mice.
High levels of dietary lutein can inhibit mammary tumor growth in mice. However, the antitumor effect of low levels of dietary lutein on mammary tumors is unavailable. Female BALB/c mice and the WAZ-2T (-SA) mammary tumor cell line were used in two experiments. A preliminary tumor cell dose titration study (Experiment 1) was designed to determine the inoculation dose to produce approximately 65% tumor incidence. Mice (n = 10/dose) were inoculated with 0 to 1 x 10(6) tumor cells in the right inguinal mammary fat pad. A tumor cell load of 2.5 x 10(3) cells/inoculation produced approximately 65% tumor incidence. This dose was used in a subsequent study (Experiment 2) of the efficacy of dietary lutein against mammary tumor development. Mice (n = 20/treatment) were fed a semisynthetic diet containing 0, 0.002, 0.02, 0.2 or 0.4% lutein from marigold extract. After 14 d, all mice were inoculated with 2.5 x 10(3) tumor cells, and tumor growth was measured daily for 70 d at which time blood, liver, spleen and tumors were obtained. Lutein + zeaxanthin uptake increased dose-dependently (P < 0.05) with dietary lutein levels from 0 to 0.02% (spleen) or 0.2% (plasma, liver and tumor). Low levels (0.002 and 0.02%) of dietary lutein lowered (P < 0.05) mammary tumor incidence, tumor growth and lipid peroxidation, and increased tumor latency, whereas higher dietary levels (0.2 or 0.4%) were less effective. Therefore, very low amounts of dietary lutein (0.002%) can efficiently decrease mammary tumor development and growth in mice.
Park
J S
JS
Program in Nutrition, Washington State University, Pullman, WA 99164-6351, USA.
Chew
B P
BP
Wong
T S
TS
D000818:Animals; D002851:Chromatography, High Pressure Liquid; D004032:Diet; D004305:Dose-Response Relationship, Drug; D005260:Female; D015227:Lipid Peroxidation / Q000187:drug effects; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D014975:Lutein / Q000008:administration & dosage / Q000378:metabolism / Q000627:therapeutic use*; D008325:Mammary Neoplasms, Experimental / Q000517:prevention & control*; D051379:Mice; D008807:Mice, Inbred BALB C; D009929:Organ Size / Q000187:drug effects; D013154:Spleen / Q000187:drug effects / Q000378:metabolism; D014407:Tumor Cells, Cultured
D014975:Lutein