Effect of micellar lipids, dietary fiber and β-carotene on lutein bioavailability in aged rats with lutein deficiency.

Objective: To determine the effect of various dietary components on the intestinal uptake of lutein in aged rats.

Methods: This study determined the time-course (2, 4, 6, 8 h) plasma and tissue responses of a pharmacologic dose of lutein (200 μM) solubilized in mixed micelles with fat (3%, soybean oil), phosphatidylcholine (PC; 3 mM), lysophosphatidylcholine (lysoPC; 3 mM), dietary fiber (pectin, 1.25%), β-carotene (200 μM), or micelles with no dietary components (control) in aged rats with lutein deficiency.

Results: No lutein was detected in the plasma of rats at 0 h indicating the deficiency. After gavages of lutein, the mean percent area under the curve (picomoles per milliliter per 8 h) of plasma lutein in the fat (91.4), PC (218.0), and lysoPC (94.1) groups were higher (P > 0.05), whereas its level in the dietary fiber and β-carotene groups was lower than the control group. The liver and eye lutein levels of the PC (95.4, 38.67%) and fat (18.2, 143%) groups were significantly higher, whereas the lysoPC (9.6, 27.2%), β-carotene (19.2, 35.4%), and dietary fiber (3.1, 88.4%) groups were lower than the control group.

Conclusion: Results indicate that soybean oil and soy phospholipids greatly sway lutein absorption in aged rats with lutein deficiency. The results also suggest that ingestion of lutein with pectin and β-carotene suppresses lutein absorption. Hence, to improve the absorption of lutein in older adults with macular pigment deficiency, foods with sufficient fat with low dietary fiber and β-carotene may be suggested.