Background: Most of the oral drugs have the properties of weak intestinal absorption and low bioavailability, which leads to little treatment to diseases. By nanotechnology, these drugs can be efficiently delivered to pass biological barriers and promote the cell uptake ability for the enhancement of the oral bioavailability.
Methods: The present work chose the prepared curcumin-loaded galactosylated albumin nanoparticles (Gal-BSA NPs) as the nano-drug samples to study the intestinal capacity and the oral bioavailability.
Results: The cell uptake assay showed that the Gal-BSA NPs could promote the internalization of more curcumin into the Caco-2 cells. Moreover, the cell uptake mechanism of Gal-BSA-Cur NPs depended on the clathrin-mediated endocytosis transport. The intestinal permeation assay using one Ussing chamber exhibited that the absorptive amounts of curcumin in Gal-BSA-Cur NPs group were 1.5-fold of pure curcumin group. Meanwhile, the permeation mechanism of Gal-BSA-Cur NPs across the intestine mainly depended on the passive transport. The pharmacokinetics study in vivo suggested that the oral bioavailability of Gal-BSA-Cur NPs was improved by 1.4-fold compared with pure curcumin.
Conclusion: All results demonstrated that Gal-BSA NPs could improve the intestinal absorption capacity and oral bioavailability of curcumin through the double absorption mechanisms of the clathrin-mediated endocytosis and the passive transport.
Keywords: intestinal absorption, galactosylated nanoparticles, oral bioavailability, absorption mechanism, curcumin