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Encapsulation of esculetin into DSPE-MPEG2000 carrier was performed to improve its water solubility and oral bioavailability, as well as enhance its anti-inflammatory effect on a mouse model of ulcerative colitis that was induced with dextran sulphate sodium (DSS). We determined the in-vitro and in-vivo high-performance liquid chromatographic (HPLC) analysis method of esculetin; Esculetin-loaded nanostructure lipid carrier (Esc-NLC) was prepared using a thin-film dispersion method, wherein a particle size analyser was used to measure the particle size (PS) and zeta potential (ZP) of the Esc-NLC, while a transmission electron microscope (TEM) was employed to observe its morphology. Also, HPLC was used to measure its drug loading (DL), encapsulation efficiency (EE) and the in-vitro release of the preparation, as well as investigate the pharmacokinetic parameters. In addition, its anti-colitis effect was evaluated via histopathological examination of HE-stained sections and detection of the concentrations of tumour necrosis factor-alpha (TNF-α), interleukin (IL)-1 beta (β), and IL-6 in serum with ELISA kits. The PS of Esc-NLC was 102.29 ± 0.63 nm with relative standard deviation (RSD) of 1.08% (with poly-dispersity index-PDI of 0.197 ± 0.023), while the ZP was −15.67 ± 1.39 mV with RSD of 1.24%. Solubility of esculetin was improved coupled with prolonged release time. Its pharmacokinetic parameters were compared with that of free esculetin, wherein the maximum concentration of the drug in plasma was increased by 5.5 times. Of note, bioavailability of the drug was increased by 1.7 times, while the half-life was prolonged by 2.4 times. In the anti-colitis efficacy experiment, the mice in Esc and Esc-NLC groups exhibited significantly reduced levels of TNF-α, IL-1β, and IL-6 in their sera comparable to the DSS group. Colon histopathological examination revealed that mice with ulcerative colitis in both Esc and Esc-NLC groups displayed improved inflammation, amid the Esc-NLC groups having the best prophylactic treatment effect. Esc-NLC could ameliorate DSS-induced ulcerative colitis by improving bioavailability, prolonging drug release time and regulating cytokine release. This observation confirmed the potential of Esc-NLC to reduce inflammation in ulcerative colitis, albeit the need for follow-up research to verify the application of this strategy to clinical treatment of ulcerative colitis. [ABSTRACT FROM AUTHOR]

Myricetin (MYR) was incorporated into pH-sensitive liposomes in order to improve its bioavailability and anti-hyperuricemic activity. The MYR pH-sensitive liposomes (MYR liposomes) were prepared using thin film dispersion method, and assessed by particle size (PS), polydispersed index (PDI), zeta potential (ZP), encapsulation efficiency, drug loading, and in vitro release rate. Pharmacokinetics and anti-hyperuricemic activities were also evaluated. The PS, PDI, ZP, encapsulation efficiency, and drug loading of MYR liposomes were 184.34 ± 1.05 nm, 0.215 ± 0.005, −38.46 ± 0.30 mV, 83.42 ± 1.07%w/w, and 6.20 ± 0.31%w/w, respectively. The release rate of MYR liposomes was higher than free MYR, wherein the cumulative value responded to pH. Besides, the Cmax of MYR liposomes was 4.92 ± 0.20 μg/mL. The level of uric acid in the M-L-H group (200 mg/kg) was reduced by 54.74%w/v in comparison with the model group. MYR liposomes exhibited pH sensitivity and could potentially enhance the oral bioavailability and anti-hyperuricemic efficacy of MYR. [ABSTRACT FROM AUTHOR]

The aim of this study was to develop licochalcone A-loaded self-microemulsifying drug delivery system (LCA-SMEDDS) to improve bioavailability and anti-hyperuricemic activity of hydrophobic natural compound licochalcone A (LCA). The prepared LCA-SMEDDS was characterised by transmission electron microscopy analysis, particle size, polymer dispersity index (PDI), zeta potential, stability tests and in vitro release analysis. LCA-SMEDDS and free LCA were orally administered to Sprague-Dawley rats to investigate respective bioavailability. The hyperuricaemia rat model was established to evaluate anti-hyperuricemic activity. The particle size, PDI, and zeta potential of LCA-SMEDDS were 25.68 ± 0.79 nm, 0.074 ± 0.024, −14.37 ± 2.17 mV. The oral bioavailability of LCA-SMEDDS was increased 2.36-fold compared with the free LCA. The uric acid level of LCA-SMEDDS group (200 mg/kg) was decreased 60.08% compared with model control group. The developed LCA-SMEDDS could be an outstanding candidate for improving oral bioavailability and anti-hyperuricemic activity of LCA. [ABSTRACT FROM AUTHOR]