Absorption Mechanism of Baicalin and Its Solid Lipid Nanoparticles on Caco-2 Cells / 中国药学杂志

ABSTRACT

OBJECTIVE: To study the absorption mechanism of baicalin (BA) and baicalin solid lipid nanoparticles (BA SLN) by establishing an in vitro Caco-2 cell model. METHODS: A Caco-2 cell model was established. The appropriate concentration of BA and BA SLN in Caco-2 cell monolayer model was screened by CCK-8 method and LDH method. The content of BA was determined by high performance liquid chromatography, and the effects of time, concentration, temperature and endocytosis inhibitor on the uptake of BA and BA SLN were studied by this model. The transport of BA and BA SLN in the presence or absence of efflux inhibitors was also investigated. The expression of efflux protein was detected by Western blot. RESULTS: At 50-150 μg·mL-1, the uptake of BA and BA SLN was concentration-dependent; at 4 to 37 ℃, the uptake of BA and BA SLN increased with increasing temperature; endocytosis inhibitor influenced the cellular uptake of BA SLN; multidrug resistance-associated protein 2 (MRP2) inhibitors and breast cancer resistance protein (BCRP) inhibitors significantly reduced BA efflux, but did not affect BA SLN efflux; blank SLN and BA SLN can reduce the expression of MRP2 and BCRP in cells. CONCLUSION: BA is taken up and transported by small intestinal epithelial cells in a passive manner, and may be accompanied by energy dependence, which is related to MRP2 and BCRP efflux. BA SLN can significantly increase the uptake of drugs in the Caco-2 cell model, which may be related to the increase of endocytic pathway uptake and inhibition of extracellular repressor expression inhibition drug efflux.