Improved oral bioavailability of breviscapine via a Pluronic P85-modified liposomal delivery system

Abstract

Breviscapine, a hydrophobic drug used for treating cardiovascular disease, was encapsulated in liposomes to improve its pharmaceutical characteristics. This study describes a novel liposome composition approach to specifically inhibit the P-glycoprotein efflux system. Breviscapine-loaded Pluronic P85-coated liposomes were prepared by the thin film hydration technique. The particle size, zeta potential and encapsulation efficiency of the formulations were characterized. In-vitro drug release and permeability of Caco-2 cells were investigated. In-vitro characteristics and pharmacokinetics of the liposomes were evaluated in rat studies. The Pluronic P85-modified liposomes dispersed individually and had an approximate diameter of 118.8 ± 4.9 nm and a zeta potential of -35.4 ± 1.5 mV. Encapsulation efficiency was more than 90%. The use of the P85-coated liposomes resulted in significantly (P<0.05) increased absorption of breviscapine in Caco-2 cells and in 5.6-fold enhancement in its oral bioavailability in rats. The P85-modified liposomes for the oral delivery of breviscapine were prepared using l-α-phosphatidylcholine (soy-hydrogenated) and cholesterol with a narrow size distribution. This method seems to effectively enhance the bioavailability of breviscapine in rats.