Promoting Effect of Polyphenols on Lutein Absorption at Different Stages during Digestion in Vitro and in Vivo

The aim of this study was to explore the effects of polyphenols on the absorption of lutein at different stages through lutein micellization, cell absorption, and in vivo absorption experiments.

The bioavailability and micellar properties of lutein under the action of polyphenols were detected using in vitro simulated digestion. The Caco-2 cell model was constructed to determine the cellular uptake of lutein and the expression of transport proteins such as scavenger receptor class B type Ⅰ (SR-BI), Niemann-Pick C1L1 (NPC1L1), and CD36 under the action of polyphenols. We also examined changes in the contents of lutein in the liver and plasma of mice with and without the action of polyphenols.

The in vitro digestion experiments showed that the bioavailability of lutein was increased by 4.3–8.0 times compared to the control group. Meanwhile, polyphenols reduced the average particle size of the lutein micelle solution and increase the absolute value of the potential and consequently change the performance of lutein micelles. Cell experiment results showed that different polyphenols increased the cell uptake of lutein by 3.2%–30.4%, and also activate the SR-BI, NPC1L1, and CD36-mediated signaling pathways. In addition, polyphenols significantly increased the lutein content in the liver and plasma of mice.

Polyphenols can promote the absorption of lutein during the micellization process and absorption in cells and in vivo.