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Coptidis rhizoma (Coptis) and its alkaloids exert various pharmacological functions in cells and tissues; however, the oral absorption of these alkaloids requires further elucidation. The present study aimed to examine the mechanism underlying the poor absorption of alkaloids, including berberine (BER), coptisine (COP), palmatine (PAL) and jatrorrhizine (JAT). An ultra-performance liquid chromatography (UPLC) method was validated for the determination of BER, COP, PAL and JAT in the above experimental medium. In addition, the apparent oil-water partition coefficient (Po/w); apparent permeability coefficient (Papp), determined using a parallel artificial membrane permeability assay (PAMPA) plate; membrane retention coefficient (R %); and effect of P-glycoprotein (P-gp) inhibitor on the Papp of the four alkaloids were investigated. The intestinal absorption rate constant (Ka) and absorption percentage (A %) of the four alkaloids were also determined. The results of the present study demonstrated that the Po/w of the four alkaloids in 0.1 mol·l-1 HCl medium was significantly higher (P<0.01), compared with those of the alkaloids in phosphate buffer (pH 7.4). The Papp of BER was 1.0-1.2x10-6 cm·s-1, determined using a PAMPA plate, and the Papp of BER, COP, PAL and JAT decreased sequentially. The concentrations of the four alkaloids on the apical-to-basolateral (AP-BL) surface and the basolateral-to-apical (BL-AP) surface increased in a linear manner, with increasing concentrations between 10 and 100 μmol. In addition, the transportation of BER on the BL-AP surface was significantly faster (P<0.01), compared with that on the AP-BL surface and, following the addition of verpamil (a P-gp inhibitor), the Papp (AP-BL) of the four alkaloids increased, whereas the Papp (BL-AP) was significantly decreased (P<0.01). The rat intestinal perfusion experiment demonstrated that the four alkaloids were poorly absorbed; however, the Ka of BER was significantly higher, compared with the three other alkaloids. Furthermore, the A % and Ka provided evidence that the absorption of BER was increased in the jejunum, compared with in the ileum. In conclusion, the four alkaloids from Coptis appeared to be poorly absorbed, determined using a shake flask, pre-coated PAMPA plates, a Caco-2 cell monolayer model and intestinal perfusion; however, absorption was higher in the jejunum than in the ileum. Among the four alkaloids, the permeability of BER was markedly higher than the others, and P-gp efflux had a significant effect on the absorption of those alkaloids. [ABSTRACT FROM AUTHOR]

Aberrant expression and function of retinoic acid receptor γ (RARγ) are often involved in the progression of several cancers. However, the role of RARγ in cholangiocarcinoma (CCA), chemoresistant bile duct carcinoma with a poor prognosis, remains unclear. In the present study, we found that RARγ was frequently overexpressed in human CCA specimens. Its overexpression was associated with poor differentiation, lymph node metastasis, high serum carbohydrate antigen 19-9 level, and poor prognosis of CCA. Downregulation of RARγ reduced CCA cell proliferation, migration, invasion, and colony formation ability in vitro and tumorigenic potential in nude mice. RARγ knockdown resulted in upregulation of cell cycle inhibitor P21, as well as down-regulation of cyclin D1, proliferating cell nuclear antigen, and matrix metallopeptidase 9, in parallel with suppression of the Akt/ NF-κB pathway. Furthermore, overexpression of RARγ contributed to the multidrug chemoresistance of CCA cells, at least in part due to upregulation of P glycoprotein via activation of the Wnt/β-catenin pathway. Molecular mechanism studies revealed that RARγ interacted with β-catenin and led to β-catenin nuclear translocation. Taken together, our results suggested that RARγ plays an important role in the proliferation, metastasis, and chemoresistance of CCA through simultaneous activation of the Akt/NF-κB and Wnt/β-catenin pathways, serving as a potential molecular target for CCA treatment. [ABSTRACT FROM AUTHOR]

In the title compound, C19H20INO, the central piperidine ring adopts a chair conformation. [ABSTRACT FROM AUTHOR]

Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that causes epidemics of debilitating disease worldwide. Currently, there are no licensed vaccines or antivirals available against CHIKV infection. In this study, we generated a novel live attenuated vaccine (LAV) candidate of CHIKV with a complete deficiency of capsid (ΔC-CHIKV). It could propagate in BHK-21 cells, and had similar antigenic properties as native CHIKV. Vaccination of either immunocompromised IFNAR-/- mice or immunocompetent C57BL/6 mice with a single dose of ΔC-CHIKV conferred complete protection upon challenge with wild type (WT) CHIKV. Taken together, this vaccine candidate appeared to be safe and efficacious, representing a novel strategy for CHIKV vaccine design. [ABSTRACT FROM AUTHOR]

This work was carried out to establish and validate the specific characteristic chromatography of Scutellaria Extract and evaluate the quality of commercial Scutellaria Extract and optimize production process parameters. Scutellaria Extract and formulation samples collected from different manufacturers were analyzed using HPLC-characteristic chromatogram. The HPLC characteristic peaks were considered to be the index for the parameters optimization in preparations of Scutellaria Extract. The chemical pattern recognization was applied for the analysis of characteristic peak data. The established characteristic fingerprint method possessed a good precision, repeatability, and stability. Ten common characteristic peaks were determined and identified in the specific chromatogram of 31 batches of Scutellaria Extract and 4 batches of formulation. The process parameters influenced the characteristic peaks area significantly. The similarity analysis results showed that after removing baicalin peak, the similarity of the characteristic chromatography of 9 samples were less than 0.90, indicating that the quality of commercial Scutellaria Extract was inconsistent. Non-parametric test result showed that the relative peaks area of the number 4, 6, 7 characteristic peaks had significant differences(P&lt;0.05), indicating the differences of the Scutellaria Extract quality were mainly reflected in the characteristic peaks 4, 6 and 7(norwogonin-7-O-glucuronide, oroxylin A-7-O-glucuronide, wogonoside, respectively). The cluster analysis accurately classified 31 extract samples and 4 formulation samples into five categories based on 10 characteristic peaks. The quality of Scutellaria Extracts was comprehensively evaluated and ranked by PCA. The result showed that the higher content of baicalin, the score value of quality(F value) was lower, and the quality of the Scutellaria Extract should be evaluated by multi-components instead of a single baicalin component. The optimized characteristic peaks method is stable and reliable. It is advantageous for the extract and formulations integrative quality control by combining the chemical pattern recognization.

Aim: To develop a safe and effective agent for cholangiocarcinoma (CCA) chemotherapy., Methods: A drug combination experiment was conducted to determine the effects of β-escin in combination with chemotherapy on CCA cells. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay was performed to determine the effects of β-escin and common chemotherapeutics on the proliferation of human CCA cells (QBC939, Sk-ChA-1, and MZ-ChA-1). Immunocytochemistry was used to detect the expression of P-glycoprotein (P-gp) protein. Luciferase reporter assay was used to detect the activation of the Wnt/β-catenin pathway. The protein levels of P-gp, pS9-GSK3β, pT216-GSK3β, GSK3β, β-catenin, and p-β-catenin were further confirmed by western blotting., Results: The drug sensitivity of QBC939 and QBC939/5-fluorouracil (5-FU) cells to 5-FU, vincristine sulfate (VCR), or mitomycin C was significantly enhanced by β-escin compared with either agent alone (P<0.05). In addition, the combination of β-escin (20 μmol/L) with 5-FU and VCR was synergic with a combination index<1. Further investigation found that the mRNA and protein expression of P-gp was down-regulated by β-escin. Moreover, β-escin induced GSK3β phosphorylation at Tyr-216 and dephosphorylation at Ser-9, resulting in phosphorylation and degradation of β-catenin. Interestingly, activation of the GSK3β/β-catenin pathway induced by Wnt3a resulted in up-regulation of P-gp, which was effectively abolished by β-escin, indicating that β-escin down-regulated P-gp expression in a GSK3β-dependent manner., Conclusion: β-escin was a potent reverser of P-gp-dependent multidrug resistance, with said effect likely being achieved via inhibition of the GSK3β/β-catenin pathway and thus suggesting a promising strategy of developing combination drugs for CCA.