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ABSTRACT: Organic anion transporters (OATs) have been proved to play important roles in the membrane transport of numerous potentially toxic xenobiotics, drugs, and endogenous metabolites. In general, OATs substrates can compete with one another for the transporter to mutually decrease renal secretion and thus delay the clearance and prolong the duration of action of each compound. Such interactions have the potential to bring about adverse outcomes for clinical cases. Therefore, it is very important to assess the molecular bioactivity to inhibit OATs during the development of new drugs and co-administration. In this work, the relationships between 45 chemicals and their corresponding hOAT1 and hOAT3 inhibitory activities were analyzed. The quantitative structure-activity relationship (QSAR) model was developed by genetic algorithm and multiple linear regression method. The predictive power of the proposed model was strictly evaluated, and the applicability domain was also defined. The proposed models were robust and satisfactory and could provide a feasible and effective tool for hOAT1 or hOAT3 inhibitor screening.
Archiv der Pharmazie 07/2012; 345(10):759-66. · 1.71 Impact Factor
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ABSTRACT: A novel transmembrane pH gradient active loading method to prepare alkaloids binary ethosomes was developed in this work.
Using this novel method, binary ethosomes containing total alkaloids extracted from Sophora alopecuroides (TASA) were prepared successfully at the temperature below the phase transition temperature (Tc) of the phosphatidyl choline
(PC). Several factors affecting this method were investigated. The qualities of the TASA binary ethosomes were characterized
by the shape, particle size, and encapsulation efficiency (EE). The percutaneous absorption study of TASA binary ethosomes
was performed using confocal laser scanning microscopy and Franz diffusion cells. The results showed that more than 90% sophoridine,
47% matrine, 35% sophocarpine, and 32% lemannine in TASA were entrapped within 1h at 40°C, with an efficiency improvement
of 8.87, 8.10, 7.63, and 7.78-fold than those observed in passive loading method. Transdermal experiments showed that the
penetration depth and fluorescence intensity of Rhodamine B from binary ethosome prepared by pH gradient active loading method
were much greater than that from binary ethosome prepared by passive loading method or hydroalcoholic solution. These results
suggested transmembrane pH gradient active loading method may be an effective method to prepare alkaloids ethosomal systems
at the temperatures below the Tc of PC.
Key wordsalkaloids-ethosomes-pH gradient-
Sophora alopecuroides
-transdermal delivery
AAPS PharmSciTech 04/2012; 11(3):1350-1358. · 1.43 Impact Factor
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ABSTRACT: The aim of this study was to investigate the effects of Pluronic F68 and Labrasol on the intestinal absorption and pharmacokinetics of rifampicin. Intestinal permeability of rifampicin with or without excipients was evaluated by an in situ single-pass perfusion method. A high-performance liquid chromatographic method was applied to study the pharmacokinetics of rifampicin with or without excipients. Labrasol or Pluronic F68 (0.1% and 0.05%, v/v), co-perfused with rifampicin (60 μg/mL), significantly increased in situ permeability. Similarly, verapamil (a typical P-gp inhibitor) also increased in situ permeability, but to a lesser extent. In vivo, the oral administration of rifampicin with or without Pluronic F68, Labrasol or verapamil resulted in statistically significant effect on t(1/2) (4.83 to 7.75, 6.42 and 7.46 h) and total body clearance (0.46 to 0.26, 0.28, 0.24 L/h/kg). In addition, Pluronic F68, Labrasol and verapamil produced minor changes in AUC(0-t), which improved 1.55-, 1.54-, and 1.73-fold in comparison to control group, respectively. These results showed that Labrasol and Pluronic F68 might inhibit the function of P-gp in the intestine, thereby increasing intestinal absorption and changing the pharmacokinetic parameters of rifampicin. Therefore, excipient selection is an important factor to consider in rational formulation design.
Archives of Pharmacal Research 11/2011; 34(11):1939-43. · 1.59 Impact Factor
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ABSTRACT: The essential oils extracted from three kinds of herbs were separated by a 5% phenylmethyl silicone (DB-5MS) bonded phase fused-silica capillary column and identified by MS. Seventy-four of the compounds identified were selected as origin data, and their chemical structure and gas chromatographic retention times (RT) were performed to build a quantitative structure-retention relationship model by genetic algorithm and multiple linear regressions analysis. The predictive ability of the model was verified by internal validation (leave-one-out, fivefold, cross-validation and Y-scrambling). As for external validation, the model was also applied to predict the gas chromatographic RT of the 14 volatile compounds not used for model development from essential oil of Radix angelicae sinensis. The applicability domain was checked by the leverage approach to verify prediction reliability. The results obtained using several validations indicated that the best quantitative structure-retention relationship model was robust and satisfactory, could provide a feasible and effective tool for predicting the gas chromatographic RT of volatile compounds and could be also applied to help in identifying the compound with the same gas chromatographic RT.
Journal of Separation Science 07/2010; 33(13):1980-90. · 2.73 Impact Factor
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ABSTRACT: A large number of herb materials contain essential oils with extensive bioactivities. In this work, an integrated simultaneous distillation-extraction (ISDE) apparatus was developed. To demonstrate its feasibility, the performance of ISDE was evaluated for the extraction of essential oil from Flos Magnoliae and compared with conventional techniques including steam distillation (SD) and simultaneous distillation-extraction (SDE). According to the product yield, the time consumed and the composition of oil, the essential oils isolated by ISDE were better than that obtained by SD and similar to those obtained by SDE. ISDE was also better than SDE due to its simple operation and lower consumption of energy and organic solvent.
Biomedical Chromatography 07/2009; 24(3):289-93. · 1.97 Impact Factor
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ABSTRACT: Ferruginol, a diterpene phenol, has recently received attention for its extensive pharmacological properties, including anti-tumor, antibacterial, cardio-protective and gastroprotective effects. In the present study, a high-performance liquid chromatographic (HPLC) method was developed for determination of ferruginol in rat plasma and applied for the pharmacokinetics study. The HPLC assay was performed with a VP ODS-C(18) column. The mobile phaseconsisted of methanol and 1% acetic acid solution (90:10, v/v). The flow rate was 1.0 mL/min, and the wavelength was set at 270 nm. This method was linear over the studied range of 0.1-10.0 microg/mL( )for ferruginol. The correlation coefficient was 0.9998. The intra-day and inter-day precisions were better than 4 and 5%, respectively. The extraction recovery and accuracy were greater than 97 and 96%, respectively. The detection limit was 30 ng/mL. The mean maximum concentration of ferruginol in rat plasma was 3.14 microg/mL at 40 min after oral administration at a dose of 20 mg/kg. Ferruginol was absorbed quickly p.o. with t(1/2)ka = 14.86 min and had a high rate of elimination with t(1/2) = 41.73 min. The pharmacokinetic process of ferruginol in rat was well described with a one-compartment model.
Biomedical Chromatography 06/2009; 23(10):1116-20. · 1.97 Impact Factor
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ABSTRACT: A high-performance liquid chromatographic (HPLC) method for determining lehmannine (LMN) in rat plasma was developed for application in the pharmacokinetics study. The plasma was deproteinized with acetonitrile that contained an internal standard and was separated from the aqueous layer by adding sodium chloride. The HPLC assay was carried out using a VP-ODS column at 40 degrees C. The mobile phase was acetonitrile-0.02 mol/L ammonium acetate buffer-triethylamine (35:65:0.04, v/v/v). The flow rate was 1.0 mL/min. The detection wavelength was set at 220 nm. The method was used to determine the concentration-time profiles of LMN in the plasma following oral administration or bolus injection of LMN aqueous solution. The pharmacokinetic parameters of LMN were calculated for the first time by Drug and Statistics 1.0 program.
Biomedical Chromatography 05/2008; 22(10):1149-54. · 1.97 Impact Factor
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ABSTRACT: A high-performance liquid chromatography (HPLC) method for determining sophoridine in rat plasma was developed for application in the pharmacokinetic studies. The plasma was deproteinized with acetonitrile that contained an internal standard (ephedrine) and was separated from the aqueous layer by adding sodium chloride and sodium carbonate. The HPLC assay was carried out using a YMC-ODS column. The mobile phase was methanol-ethanol-0.01 moll(-1) ammonium acetate buffer-triethylamine (10:0.5:89.5:0.03, v/v/v/v) (pH 6.80). The flow rate was 0.8 ml min(-1). The detection wavelength was set at 210 nm. The method was used to determine the concentration-time profiles of sophoridine in the plasma following oral administration or injection of sophoridine aqueous solution. The fractions of sophoridine reaching the systemic circulation were estimated for the first time by a deconvolution method.
Journal of Chromatography B 11/2006; 843(1):10-4. · 2.89 Impact Factor
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ABSTRACT: To study the chemical Constituents in the root of Rheum glabricaule.
Compounds were isolated by various column chromatographies with sillica gel. Their structures were identified by spectral analysis (MS, 1HNMR, 13 CNMR) and chemical evidences.
Seven compounds were isolated from this plant, including n-hexacosnic acid (I), palmitic acid (II), daucosterol (III), chrysophanol-8-Me ether (IV), citreorosein (V), chrysophanol 8-O-beta-D-glucopyranoside (VI) and 2,5-dimethyl-7-methoxychromone (VII).
All above compounds are obtained from this plant for the first time.
Zhong yao cai = Zhongyaocai = Journal of Chinese medicinal materials 09/2005; 28(8):658-60.
