Fructo-oligosaccharides from Morinda officinalis remodeled gut microbiota and alleviated depression features in a stress rat model.

BACKGROUND: Inulin-type fructo-oligosaccharides (FOSs) purified from Morinda officinalis How., an effective oral antidepressant for mild to moderate depression, have a largely unknown efficacy and poor bioavailability. PURPOSE: Therefore, the microbiota-gut-brain axis was used to investigate the antidepressive properties of FOSs at the interface of the gut microbiota (GM). STUDY DESIGN AND METHODS: FOSs was introduced via intragastric gavage to rats exposed to chronic unpredictable mild stress (CUMS), and the antidepressive effects were investigated through behavioral tests, intestinal morphology and corticosterone levels. Bacterial genomic DNA was extracted from feces, and the GM was profiled for using enterobacterial repetitive intergenic consensus (ERIC)-PCR analysis, partial least squares-discriminant analysis (PLS-DA) and 16S rRNA gene pyrosequencing. RESULTS: It was observed that FOSs alleviated depression-like behaviors and repaired intestinal epithelia damages. FOSs treatment lowered corticosterone levels in the plasma and urine of the model rats. Moreover, the GM compositions of normal and model rats were distantly clustered and were mainly related to the disappearance of beneficial bacteria (e.g., Acinetobacter, Barnesiella, Coprococcus, Dialister, Lactobacillus, and Paenibacillus) and appearance of depression-associated bacteria (e.g., Anaerostipes, Oscillibacter, Proteobacteria, and Streptococcus) in depressive rats. Interestingly, the dysbiosis in depressive rats' gut was reinstated with FOSs treatments. Notably, FOSs promoted the abundance of the bacterial phylum Cyanobacteria, a group of bacteria known for the secretion of pharmacologically important metabolites, such as H2S, that exhibit antidepressant-like properties. Apparently, FOSs-induced modulation of GM was more antidepressive compared to a component of FOSs, degrees of polymerization (DP) 5, and fluoxetine, the standard antidepressant drug. CONCLUSION: In conclusion, this study implied that antidepressant efficacy of FOSs was inseparable from and strongly associated with the modulation of the host' s GM.

Development and application of bio-sample quantification to evaluate stability and pharmacokinetics of inulin-type fructo-oligosaccharides from Morinda Officinalis.

Inulin-type fructooligosaccharides (FOS) purified from Morinda Officinalis, with degrees of polymerization (DP) from 3 to 9, have been approved in China as an oral prescribed drug for mild and moderate depression episode, while the stability and oral absorption of this FOS mixtures are largely unknown. As the main active component and quality control marker for above FOS, DP5 was selected as the representative FOS in this study. Desalting method by ion exchange resin was developed to treat bio-sample, followed by separation and quantification by high performance liquid chromatography-charged aerosol detector. Results showed that the DP5 was stepwisely hydrolyzed in simulated gastric fluid and gut microbiota, while maintained stable in intestinal fluid. DP5 has poor permeability across Caco-2 monolayer with Papp of 5.22 × 10-7 cm/s, and very poor oral absorption with bioavailability of (0.50 ±â€¯0.12)% in rat. In conclusion, FOS in Morinda Officinalis demonstrated poor chemical stability in simulated gastric fluid and human gut microbiota, and low oral absorption in rats.

Modified Release and Improved Stability of Unstable BCS II Drug by Using Cyclodextrin Complex as Carrier To Remotely Load Drug into Niosomes.

In answering to the challenge of enzymatic unstability of Biopharmaceutics Classification System (BCS) class II drugs, an effective remote loading strategy was developed to successfully incorporate the drug-cyclodextrin (CD) complex into niosomes to modify the release and stability of a drug candidate, pseudolaric acid B (PAB). Judged by binding constants, and combined solubilization effects of pH and CD complexation on PAB at different pH, the complex internalization driven by a transmembrane pH gradient (from 2.0 to 7.4) and the dynamic shifting of PAB-CD complexation equilibrium at this gradient were introduced. The transfer of PAB-CD complex into the internal aqueous phase of niosomes at 60 °C was primarily verified by synchrotron radiation Fourier transform infrared spectroscopy. The remote loading samples behaved as retarded release at pH 5.8, 6.8, and 7.4, for which the stability of PAB in rat plasma was significantly enhanced (about 8.1-fold), in comparison with niosomes prepared by the passive and lipid bilayer loading of PAB. The drug-carrier interaction based release modeling was further fitted, and the convection rate constant (ks) and free energy difference between free and bound states (ΔG) indicated the strongest PAB-carrier interactions in remote loading niosomes. The remote loading strategy also reduced the CD-cholesterol interaction and provided better physical stability of the system. In conclusion, the remote loading of drug-CD complex into niosomes provides advantages to modify the release and enhance the stability of unstable BCS class II drug.

Bioactivity assay of porcine relaxin based on cAMP accumulation in THP-1 cells quantified by LC-MS/MS.

This study describes a reliable bioactivity assay of porcine relaxin (pRLX) based on cyclic adenosine 3',5'-monophosphate (cAMP) accumulation in the human monocyte cell-line quantified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). As a result, the LC-MS/MS was based on a positive selected reaction monitoring of cAMP with a stable internal standard, 8-Br-cAMP and a protein precipitation procedure by HClO4. The standard curve of cAMP was linear from 5.0 ng mL(-1) to 992.0 ng mL(-1), with lower limits of detection and quantification of 0.5 ng mL(-1) and 5.0 ng mL(-1), respectively. The satisfactory validation data including stability assay were obtained. When measured by the LC-MS/MS, the pRLX sample showed a time- and dose-dependent stimulation of cAMP with the concentration for 50% of the maximal effect (EC50) of 40.6 ng mL(-1). The developed method indicated higher precision and selectivity than the commercial enzyme linked immunosorbent assay kits, which showed EC50 of 66.6 ng mL(-1).

Dramatic improvement of the solubility of pseudolaric acid B by cyclodextrin complexation: preparation, characterization and validation.

As one of the most important technologies to improve the solubility of poorly water-soluble drugs, the solubilization effects of cyclodextrins (CDs) complexation are, on occasions, not as large as expected, which tends to detract from the wider application of CDs. In this study, a dramatic improvement of the solubility of pseudolaric acid B (PAB) by CDs has been found with a 600 fold increase by HP-ß-CD complexation. In addition, the solubility enhancement of PAB by various CDs, including α-CD, ß-CD, γ-CD, HP-ß-CD and SBE-ß-CD was investigated by phase solubility studies. The inclusion complex of PAB/HP-ß-CD was prepared by different methods and characterized by differential scanning calorimetry (DSC), powder X-ray diffractometry (XRD), nuclear magnetic resonance spectroscopy ((1)H NMR) together with molecular simulation. The results indicated that the solubility of PAB was increased to 15.78mgmL(-1) in the presence of 30% HP-ß-CD, which is a 600 fold increase compared with that in pure water. And the chemical stability of PAB in PBS (pH 7.4) can be enhanced. The results of DSC and XRD showed the absence of crystallinity in the PAB/HP-ß-CD inclusion complex prepared by the saturated water solution method. The results of (1)H NMR together with molecular simulation indicated the conjugated diene side-chain of PAB was included into the cavity of HP-ß-CD, with the free energy of -20.34±4.69kJmol(-1). While the enzymatic degradation site of the carboxyl polar bond is located in the hydrophilic outer of HP-ß-CD resulted in no significant difference for the enzymatic degradation rate between PAB and PAB/HP-ß-CD complexes in rat plasma. In summary, the PAB/HP-ß-CD inclusion complex prepared in this study can greatly improve the solubility and chemical stability of PAB, which will result in the in vivo administration of PAB as a liquid solution.

Multianalyte determination of the kinetic rate constants of drug-cyclodextrin supermolecules by high performance affinity chromatography.

The kinetics of the dissociation is fundamental to the formation and the in vivo performance of cyclodextrin supramolecules. The individual determination of the apparent dissociation rate constant (kd,app) using high performance affinity chromatography (HPAC) is a tedious process requiring numerous separate studies and massive data fitting. In this study, the multianalyte approach was employed to simultaneously measure the kd,app values of three drugs through one injection based on the investigation of the dependence of drug-cyclodextrin interaction kinetics on the mobile phase composition. As a result, the kd,app values increased when decreasing the ion strength, increasing the ionization of drugs and adding extra organic solvents. The values of kd,app for acetaminophen, phenacetin and S-flurbiprofen estimated by the multianalyte approach were 8.54±1.81, 5.36±0.94 and 0.17±0.02s(-1), respectively, which were in good agreement with those determined separately (8.31±0.58, 5.01±0.42 and 0.15±0.01s(-1)). For both of the single and multiple flow rate peak profiling methods, the results of the multianalyte approach were statistically equivalent with that of the single compound analysis for all of the three drugs (p>0.05). The multianalyte approach can be employed for the efficient evaluation of the drug-cyclodextrin kinetics with less variance caused by cyclodextrin column bleeding.