Licorice chalcone A (LCA) possesses a variety of pharmacological activities amid poor solubility in water which consequently restricts its clinical application. In this study, LCA micelles (LCA-M) and LCA micelles modified with TPGS (LCA-M-T) were prepared, wherein in vitro, in vivo, and hepatoprotection potential of the formulations were evaluated. LCA-M-T and LCA-M were prepared by thin-film dispersion method and characterized by a transmission electron microscope (TEM). The encapsulation efficiency, in vitro release, and stability of LCA-M-T and LCA-M were detected by HPLC and UV, respectively. The pharmacokinetics, tissue distribution studies, and pharmacodynamics research were also carried out after oral administration. The sizes of micellar particles were 34.02 ± 0.29 nm (LCA-M) and 62.46 ± 0.51 nm (LCA-M-T) with 0.223 ± 0.021 (LCA-M) and 0.343 ± 0.006 (LCA-M-T) polydispersities, − 35.06 ± 2.27 mV (LCA-M) and − 38.58 ± 1.69 mV (LCA-M-T) zeta potentials, and 95.2 ± 0.27% (LCA-M) and 90.34 ± 0.31% (LCA-M-T) encapsulation efficiencies. The drug loadings were 8.56 ± 0.27% (LCA-M) and 8.04 ± 0.19% (LCA-M-T). The two preparations released quickly and reached over 95% in the four-dissolution media (pH = 1.2 pH = 6.8 pH = 7 pH = 7.4). The preparations of LCA showed significant elevation of cumulative release compared with the free LCA and more importantly 119% (LCA-M) and 285% (LCA-M-T) increments in the relative oral bioavailability of the drug. Preparations of LCA may act as a promising approach to improve solubility and enhance bioavailability and liver protective activity of LCA.

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.

Hyperlipidemia has become a common disease in modern society with its prevalence becoming relatively high in the world. A series of complications that accompany hyperlipidemia are seriously threatening individuals' health. Dihydromyricetin (DMY) is a kind of polyphenol hydroxy (OH) dihydroflavonol extracted from the stems and leaves of Ampelopsis grossedentata. It has a variety of pharmacological activities. This study aims to develop a self-microemulsifying drug delivery system (SMEDDS) to improve the oral bioavailability of DMY, and to evaluate its hypolipidemic activity. The self-microemulsion drug delivery system is composed of medium chain triglyceride (MCT, oil phase), Tween 80 (emulsifier), and PEG 200 (coemulsifier). The prepared DMY-SMEDDS has stable physical and chemical properties, small droplet size (15.49 +/- 0.15 nm), good polydispersity index (PDI = 0.160 +/- 0.010), negative zeta potential (-17.37 +/- 0.09 mV), and high encapsulation efficiency (98.04 +/- 0.25%). The results of in vitro dissolution and in vivo pharmacokinetics show that the prepared DMY-SMEDDS significantly improve the solubility of DMY in aqueous medium, while its oral bioavailability is 2.34 times higher than that of free drug. In conclusion, the DMY-SMEDDS prepared in this study prospectively improves the solubility and oral bioavailability of DMY also enhance the therapeutic effect.

This study sought to prepare a self-microemulsion drug delivery system containing zingerone (Z-SMEDDS) to improve the low oral bioavailability of zingerone and anti-tumor effect. Z-SMEDDS was characterized by particle size, zeta potential and encapsulation efficiency, while its pharmacokinetics and anti-tumor effects were also evaluated. Z-SMEDDS had stable physicochemical properties, including average particle size of 17.29 ± 0.07 nm, the zeta potential of -22.81 ± 0.29 mV, and the encapsulation efficiency of 97.96% ± 0.02%. In vitro release studies have shown the release of zingerone released by Z-SMEDDS was significantly higher than free zingerone in different release media. The relative oral bioavailability of Z-SMEDDS was 7.63 times compared with free drug. Meanwhile, the half inhibitory concentration （IC50）of Z-SMEDDS and free zingerone was 8.45 μg/mL and 13.30 μg/mL, respectively on HepG2. This study may provide a preliminary basis for further clinical research and application of Z-SMEDDS.

In the present study, a novel nonionic surfactant vesicles (NSVs) system consisting of cholesterol, Tween 80 and Span 80 was developed for the delivery of Ginsenoside Rb-1 with an improved oral bioavailability. The prepared vesicles were hollow and spherically shaped with acceptable diameter (264.68 +/- 4.17 nm), zeta potential (-11.58 +/- 0.87 mV) and encapsulation efficiency (69.034 +/- 0.045%). XRD analysis provided affirmed the encapsulation of Rb-1 in the vesicles. The in vitro release profile of Rb-1 from the vesicles in the two different media (double distilled water, pH 7.0, phosphate buffer solution, pH 7.4) showed statistical insignificant difference when compared with the free Ginsenoside Rb-1. Notably, the pharmacokinetic analysis of optimized Ginsenoside Rb-1-NSVs exhibited a higher C-max (9.55 +/- 0.5 mu g/mL versus 6.22 +/- 0.53 mu g/mL) with 1.82-fold increase in relative oral bioavailability. Collectively, these findings revealed that the developed vesicles could be a novel alternative in improving the oral bioavailability of Ginsenoside Rb-1 and extending its application in the clinical setting.