Study on the bioavailability of stevioside-encapsulized lutein and its mechanism

This study aims to develop novel lutein nanoparticles encapsulized by stevioside (LUT-STE, 165 ? 2 nm average particles size) and systematically evaluate its bioavailability. Multiple spectroscopy and NMR analyses showed lutein and stevioside could interact through hydrogen bonds, C?H?n interaction and van der Waals forces. Molecular docking simulation showed lutein was well distributed in the hydrophobic cavity of stevioside. Analyzed by Caco-2 cellular models, the transported amount of LUT-STE was 2.39 times that of lutein in 120 min with a Papp (B ? A)/Papp (A ? B) value of 0.63 ? 0.04. Nystatin and dynasore significantly reduced the cellular uptake of LUT-STE by 41.3% and 57.7%, respectively. Compared with free lutein, LUT-STE increased the Cmax in mice plasma by 5.01-fold and promoted the accumulation in multiple organs. LUT-STE promoted the protein expressions of CD36, NPC1L1 and PPAR? in both cell and animal models. In conclusion, stevioside entrapment significantly promote the bioavailability of lutein through multiple transmembrane pathways.

Automated summary

This study successfully developed lutein nanoparticles encapsulated by stevioside, demonstrating significant improvement in lutein bioavailability through multiple transmembrane pathways. The interactions between lutein and stevioside, as well as the promotion of protein expressions in both cellular and animal models, contribute to the enhanced absorption and distribution of lutein in vivo.