Enhancement of oral bioavailability and anti-hyperuricemic activity of aloe emodin via novel Soluplus®—glycyrrhizic acid mixed micelle system
The objective of this study was to fabricate a novel drug delivery system using Soluplus® (polyvinyl caprolactam–polyvinyl acetate–polyethylene glycol graft copolymer) and glycyrrhizic acid to improve solubility, bioavailability, and anti-hyperuricemic activity of aloe emodin (AE). The AE-loaded mixed micelles (AE-M) were prepared by thin-film hydration method. The optimal AE-M contained small-sized (30.13 ± 1.34 nm) particles with high encapsulation efficiency (m/m, %) of 90.3 ± 1.08%.
The release rate of AE increased in the micellar formulation than that of free AE in the four media (DDW, pH 7.0; phosphate buffer solution, pH 7.4; phosphate buffer solution, pH 6.8; and hydrochloric acid aqueous solution, pH 1.2). In comparison to free AE, the pharmacokinetic study of AE-M showed that its relative oral bioavailability increased by 3.09 times, indicating that mixed micelles may promote gastrointestinal absorption. More importantly, AE-M effectively reduced uric acid level by inhibiting xanthine oxidase (XOD) activity in model rats.
The degree of ankle swelling, serum levels of interleukin (IL)-1, and IL-6-related inflammatory factors levels all decreased in the gouty arthritis model established via monosodium urate (MSU) crystals. Taken together, the AE-M demonstrated the potential to improve the bioavailability, anti-hyperuricemic activity, and anti-inflammation of AE.
Article information: Shi, F., Chen, L., Wang, Y. et al. Enhancement of oral bioavailability and anti-hyperuricemic activity of aloe emodin via novel Soluplus®—glycyrrhizic acid mixed micelle system. Drug Deliv. and Transl. Res. (2021). https://doi.org/10.1007/s13346-021-00969-8