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OBJECTIVE@#To synthesize 3, 5, 4' -trimethoxystilbene (TMS) by methylation of resveratrol (Res), a natural compound extracted from polygonum cuspidatum, to identify the chemical structure of TMS, to test its pharmacokinetics, and to determine the effects of TMS on the growth inhibition and apoptosis in pulmonary artery smooth muscle cells (PASMCs).@*METHODS@#The chemical structure of TMS was analyzed by UV- and IR- absorption spectrometry, (1)H-NMR and (13)C-NMR spectroscopy and mass spectrometry. We measured the bioavailability, the characteristics of intestinal absorption, and the distribution of TMS in body and excretions of SD rats after oral administration of TMS. The acute toxicity of TMS in mice was tested. PASMCs were prepared from pulmonary artery of SD rats. The PASMCs were divided into 8 groups. Group of A (control) was cultured without TNF-α, TMS, or Res. Group of B (TNF-α) was cultured with 100 pg/mL TNF-α. Groups of C-E (low-high concentrations of TMS) were cultured with 100 pg/mL TNF-α and 5, 10, 20 μmol/L TMS, respectively. Groups of F-H (low-high concentrations of Res) were cultured with 100 pg/mL TNF-α and 50, 100, 200 μmol/L Res, respectively. The proliferation of PASMCs after treatment was determined by MTT assay. The apoptosis of PASMCs after treatment was determined by flow cytometry.@*RESULTS@#The UV absorption map of TMS showed λmax(MeOH) at 318, 306.2, and 217.8 nm. Analysis of infrared spectrum of TMS showed IRvKBr max /cm at 2999, 2935, 2836, 1591, 1511 and 1456/cm. The (1)H-NMR map showed that the synthetic product contained three hydroxy groups, while (13)C-NMR map showed 17 carbon signals and some symmetrical structural fragments. Electospray ionization mass spectrometry of the productshowed m/z peaks corresponded to 271[M+H](+), 256[M+H-CH(3)](+) and 241[256-CH(3)](+); the implied relative molecular weight is 270 and the implied molecular formula is C17H18O3. These data confirm the product is 3,5,4' - trimethoxystilbene. The absolute bioavailability of TMS was 45.4%. TMS was well absorped in the upper small intestine; it was excreted in stool and bile and distributed into several tissues. The maximal tolerance dose (MTD) of TMS was 5.85 g/kg. MTT assay showed TMS inhibited the proliferation of PASMCs in a dose-dependent manner. The extent of growth inhibition in A-H groups were (4.07±2.12)%, (6.54±4.78)%, (9.35±4.26)%, (16.75±5.34)%, (23.74±7.07)%, (6.78±5.58) %, (8.81±5.16) %, and (17.81±6.03) %, respectively. Flow cytometry showed the extent of apoptosis in PASMCs (after being treated with TMS for 24 h) was significantly higher than that in PASMCs treated only with TNF-α. The apoptosis rates of A-H groups were (2.63±0.74)%, (3.54±0.81)%, (5.77±4.62)%, (11.68±5.35)%, (18.79±4.15)%, (4.11±3.59)%, (6.33±4.8) %, and (12.47±5.06)%, respectively.@*CONCLUSION@#We have confirmed our synthetic product as 3,5,4'-trimethoxystilbene (TMS), with the molecular formula of C17H18O3 and appropriate molecular weight and absorbption and NMR spectra. The bioavailability of TMS was to 45%. It strongly inhibits the proliferation of PASMCs in a dose-dependent manner and induces apoptosis of PASMCs.
Subject(s)
Animals , Male , Rats , Anti-Inflammatory Agents , Pharmacology , Apoptosis , Cell Proliferation , Cells, Cultured , Myocytes, Smooth Muscle , Cell Biology , Metabolism , Pulmonary Artery , Cell Biology , Metabolism , Rats, Sprague-Dawley , Resveratrol , Stilbenes , Chemistry , Pharmacokinetics , PharmacologyABSTRACT
This study is to screen 23 blank O/W type microemulsion (ME) samples, that is 15 samples from our laboratory, and 8 samples from literature; compare the conductivity-water content curve (CWCC) method and visual method in determining the critical water content during O/W type MEs' formation, to analyze the deficiency and the feasibility of visual method and to exploxe scientific meanings of CWCC method in judging the critical water content of O/W type MEs during formation. The results show that there is a significant difference between the theoretical feasible CWCC method and visual method in determining the critical water content (P<0.001), and the results judged by conductivity is higher than that by eye-based water content. Therefore, this article firmly confirmed the shortcomings of visual method and suggested that the eye-base "critical water content" may falls into continuous ME stage during O/W MEs' formation. Further more, the CWCC method has theoretical feasibility and scientific meanings in determining the critical water content of O/W type MEs during formation.
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This paper described a rapid and se nsitive HPLC method to analyze (E)-3, 5,4'-trimethoxystilbene (BTM-0512) in rat plasma and tissues. The analysis used a BDS Hypersil C18 analytical column (250 mm×4.6 mm ID, 5 μm) and acetonitrile / water as the mobile phase. The UV detection wavelength was 319 nm. Proteins were precipitated with acetonitrile and diethylstilbestrol as internal standard. The method was validated according to State Food and Drug Administration of China and ICH of Technical Requirements for Registration of Pharmaceuticals for Human Use Guidelines. The limit of interday precision values (%RSD) were in the range of 2.6% -5.1% and 2.4% -4.8%, respectively.Mean accuracy and absolute recoveries of BTM-0512 ranged from 95.3% - 100. 1% and 95.9% -100.9% for plasma and tissues, respectively. This method can be quite useful for BTM-0512 pharmacokinetic and tissue distribution studies, for purpose which multiple plasma and tissue samples can be analyzed quickly with high reproducibility.
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OBJECTIVE:To study the main factors affecting in vitro dissolubility of total puerariae flavones(TPF)bioad?hesive tablets.METHODS:Using HPMC,Carbopol(CP934NP)as bioadhesive and base materials,lactose as porogenic agent to prepare bioadhesive tablets;Basket-rotating method was adopted to determine the dissolubility while0.1mol/L HCl was used as dissolution medium,Rotational speed was100r/min.The accumulated dissolution was detected and the influence of the amount of HPMC,CP,kind of porogenic agent,amount of lactose,size of granules in pressed tablets and medium pH on dissolubility was observed.RESULTS&CONCLUSION:The amount of HPMC,CP and lactose,kind of porogenic agent,size of granules in tablets and medium pH can affect the dissolubility of bioadhesive tablets.
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OBJECTIVE:To study the dissolution rate of total puerariae flavones(TPF)bioadhesive sustained-release tablet,and to determine its bioadhesive force to animal stomach and small intestine in vitro METHODS:Using rotating basket method,the dissolubility summation was determined with 0 1mol/L HCl as dissolution medium at speed of 100r/min,single-index model,Weibull distributing model,Higuchi equation and zero-class model were used to imitate the dissolution curve The biggest absolute error,the biggest relative error and AIC were used as comprehensive indices to select the best imitating model A new apparatus made by ourselves was used to compare the adhesive force between the sustained-release tablets and popular tablets in adhering to rabbits'stomach or small intestine RESULTS:The results showed that the dissolution rate in vitro imitated in single-index model was the best Bioadhesion study showed that there were obvious differences between bioadhesive sustained-release tablets and non-bioadhesive tablets in adhering with gastric mucosa and small intestines mucosa(P
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Objective To screen the active cardiovascular components from Rhizoma Polygonati and to observe the effect on myocardial ischemia rat.Methods The active components from Rhizoma Polygonati were extracted by system solvent separation methods,and their cardiovascular effects on the rat models induced by subcutaneous injection of isoproterenol were tracked to find out the optimal active cardiovascular components.Results Among the extracts from Rhizoma Polygonati,the n-Butanol(EB)extract which consisted of glycosides and aglycons,was the best active cardiovascular component;aqueous extract which consisted of alkaloids,flavonoids,glycosides and aglycons,was the better component;the emulsion of Rhizoma Polygonati,which consisted of petroleum ether extract,chloroform extract and water-ethanol extract had less cardiovascular activity.Conclusions The parts with medium polarity from Rhizoma Polygonati have the best cardiovascular activities.
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OBJECTIVE:To investigate the technique of purifying the total flavones of Radix Puerariae,so as to provide an experimental basis for extraction and purification of the flavones METHODS:Five purifying methods,including adsorption with macroreticular adsorption resin AB-8,D101,D201 and with polyamide,extration with n-butanol,were adopted,and the amount and purity of total flavones collected and preservation of the components of total flavones were compared RESULTS:By using the above-mentioned five methods,the percentages of the contents of total flavones were 89 4%,83 6%,91 0%,96 0% and 82 9% and the recoveries of products were 79 3%,64 2%,88 0%,55 7% and 77 2% respectively CONCLUSION:Among the five methods,adsorption with AB-8 macroreticular adsorption resin is the best,which may be used for purification of total flavones of Radix Puerariae