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1.
AIM: To investigate the absorption characteristics of the total alkaloids from Mahoniae Caulis (TAMC) through the administration of monterpene absorption enhancers or protein inhibitors. METHOD: The absorption behavior was investigated in an in situ single-pass intestinal perfusion (SPIP) assay in rats. RESULTS: The intestinal absorption of TAMC was much more than that of a single compound or a mixture of compounds (jatrorrhizine, palmatine, and berberine). Promotion of absorption by the bicyclic monoterpenoids (borneol or camphor) was higher than by the monocyclic monoterpenes (menthol or menthone), and promotion by compounds with a hydroxyl group (borneol or menthol) was higher than those with a carbonyl group (camphor or menthone). The apparent permeability coefficient (Papp) of TAMC was increased to 1.8-fold by verapamil, while it was reduced to one half by thiamine. The absorption rate constant (Ka) and Papp of TAMC were unchanged by probenecid and pantoprazole. CONCLUSION: The intestinal absorption characteristics of TAMC might be passive transport, and the intestinum tenue was the best absorptive site. In addition, TAMC might be likely a substrate of P-glycoprotein (P-gp) and organic cation transporters (OCT), rather than multidrug resistance protein (MRP) and breast cancer resistance protein (BCRP). Compared with a single compound and a mixture of compounds, TAMC was able to be absorbed in the blood circulation effectively.  相似文献   

2.
OBJECTIVE: To better understand the working mechanism of acupuncture, we investigated the skin electrical impedance distribution around acupoints, and the impedance changes at 12 original acupoints bilaterally after bending the limbs.METHODS: We measured the skin electrical impedance in three study subjects in the frequency range of 40 to 10 k Hz using the four-electrode method with a sharp probe and a large reference electrode.A measurement matrix of 7 mm × 7 mm with spacing of 2.0(or 3.0) mm was measured to obtain 2 D impedance mapping of acupoints. The impedance spectra of 12 original acupoints were measured at the 0° position and the 90° position.RESULTS: The electrical impedance of some acupoints, such as Yangchi(TE 4), was 16 times lower than that of the surrounding area, showing a recognizable small central area of low impedance with a diameter of less than 4 mm. In contrast, other acupoints, such as Laogong(PC 8), had an electrical impedance that was not significantly different from that of the surrounding area. When the limb was bent from a straight position(0o) to a vertical position(90o), the electrical impedance of the 12 original acupoints showed varied trends, either increasing or decreasing by a factor of up to ten times, or remaining at the same level.CONCLUSION: Not all acupoints tested show the property of low impedance, which might be related to the varied depth of the openings of superficial collaterals. The unexpected dependence of acupoint impedance on limb angle is a novel discovery, which implies that the channel paths are located in interstitial structures in the limbs. It might be possible to determine an optimized limb position for each particular acupuncture treatment in clinical practice.  相似文献   

3.
Objective: In order to find lead compound with anti-HBV activity from peroxo-bridged diosgenin derivatives obtained with Eosin Y as the photosensitizer.Method: Eosin Y was used as the photosensitizer to activate the oxygen in the air to synthesize novel diosgenin derivatives with peroxo-bridge.The structures of synthesized compounds were identified by NMR and HR-MS.Their cytotoxicity and antihepatitis B activity were evaluated via MTS assay and ELISA method,respectively.Results: Six diosgenin derivatives were synthesized,three of which contained peroxo-bridge,and their structures were confirmed by spectroscopy.It showed that 5 α,8 α-peroxo-6-alkenyl-diosgenin(7)could suppress the production of HBs Ag on transfected HepG2.2.15 cells at low-toxic concentration and the inhibition rate on HepG2.2.15 cells was 18.28% at 12.50 μg/mL,better than that of 3 TC(7.30% at 12.50 μg/mL)and others.Conclusion: Due to its lower cytotoxicity and potential anti-hepatitis B activity,compound 7 could be developed as the promising candidate of anti-hepatitis B drug.It also indicated that the peroxo-bridged derivatives had potential biological values for developing clinical agents.  相似文献   

4.
This study investigated effects of Ginsenoside Ro(Ro) on interleukin-1β(IL-1β)-induced apoptosis and inflammation in rat chondrocytes. The rat chondrocytes were co-treated with IL-1β(10 ng·kg-1) and Ro(50, 100 and 200 μmol·L-1) for 48 h. Chondrocytes viability was detected by the MTT assay and Annexin V-FITC/PI dual staining assay. Caspase 3 activity was measured by using caspase 3 colorimetric assay kit. Apoptosis related proteins Bax, Bad, Bcl-xL, PCNA, p53 and phospho-p53, along with inflammation related protein MMP 3, MMP 9 and COX-2, and the expression of phospho-NF-κB p65 were assayed by western blotting analyses. Ro could improve IL-1β-induced chondrocytes viability. Ro could suppress IL-1β-induced apoptosis by inhibiting levels of Bax and Bad, decreasing p53 phosphorylation and promoting the expression of Bcl-xL and PCNA. Ro inhibited caspase 3 activity. IL-1β-induced inflammation and matrix degration were also alleviated by Ro with down-regulating the expression of MMP 3, MMP 9 and COX-2. Moreover, Ro inhibited NF-κB p65 phosphorylation induced by IL-1β. In conclusion, these results suggested Ro exerted anti-apoptosis and anti-inflammation in IL-1β-induced rat chondrocytes, which might be related to NF-κB signal pathway. Therefore, we propose that Ro might be a potential novel drug for the treatment of osteoarthritis.  相似文献   

5.
Monoclonal antibodies (MAbs) against natural products with low?molecular weights have become an important tool when combined with other analytical systems. Eastern blotting involves a typical staining system wherein, for example, glycosides can be blotted to a membrane and cross?linked and stained using MAbs. An immunoaffinity column combined with a monoclonal antibody allows a one?step purification of hapten compounds or preparation of a knockout extract that removes only the target hapten molecules from a crude extract. Here, we discuss the application of these extracts. Single?chain variable fragment (scFv) proteins have led to novel assay systems such as fluobodies or antibodies coupled with green fluorescent protein for natural products. A typical novel application of a scFv gene would be in the context of plant breeding; this is designated “missile?type” molecular breeding, intended to increase hapten molecule concentrations in transgenic plants  相似文献   

6.
AIM: Variation in structure-related components in plant products prompted the trend to establish methods, using multiple or total analog analysis, for their effective quality control. However, the general use of routine quality control is restricted by the limited availability of reference substances. Using an easily available single marker as a reference standard to determine multiple or total analogs should be a practical option. METHOD: In this study, the Ultra-HPLC method was used for the baseline separation of the main components in ginseng extracts. Using a plant chemical component database, ginsenosides in ginseng extracts were identified by Ultra-HPLC-MS analysis. The charged aerosol detection(CAD) system with post-column compensation of the gradient generates a similar response for identical amounts of different analytes, and thus, the content of each ginsenoside in ginseng extracts was determined by comparing the analyte peak area with the reference standard(determination of total analogs by single marker, DTSM). The total ginsenoside content was determined by the summation of reference standard and other ginsenoside components. RESULTS: The results showed that DTSM approaches were available for the determination of total ginsenosides in a high purity ginseng extract because of the removal of impurities. In contrast, DTSM approaches might be suitable for determination of multiple ginsenosides without interference from impurities in the crude ginseng extract. CONCLUSION: Future practical studies similar to the present study should be conducted to verify that DTSM approaches based on CAD with post-column inverse gradient for uniform response are ideal for the quality control of plant products.  相似文献   

7.
Objective The amount of nuclear DNA(C-value)is a key biodiversity character that provides strong unifying elements in revealing the phylogenetic regularity and relationship between genome size and functional traits for plant resource.The estimation of C-values could primarily extend our knowledge on the genetic background and genome diversity for medicinal plants,and thereby the variation of pharmacological constituents and phylogenetic mechanism of medicinal plant taxa will be revealed.However,a large number of medicinal plants(e.g.Cornus officinalis)typically contain a series of secondary metabolites,especially tannic acid,which would significantly affect the estimation of DNA content by flow cytometry(FCM).Methodological discussions and improvement need to be made to solve this problem.Methods Two isolation buffers LB01 and Otto 1 were selected to prepare nuclear suspension with additional treatments of pre-soaking and centrifugation combination of gradient centrifugal force and duration.The best isolation and estimation methods were determined by FCM measurement in C.officinalis.Results The dry leaves were pre-soaked in Otto I buffer for 15 min and the Otto I nuclear suspension was centrifugated at 1.0×103 g for 2 min.The results showed that debris and nuclei were better separated and the scatterplots of good quality were obtained with low coefficient of variation(CV).Contrarily,the nuclear DNA content of C.officinalis could not be accurately estimated for nuclei extracted by LB01 buffer.Finally,2C-value and genome size of C.officinalis were first estimated as 5.92 pg and 2893 Mbp,respectively.Conclusion The new methods proposed here are able to accurately estimate DNA content of C.officinalis,which provides valuable references for the estimation of genome size in other tannin-rich medicinal plants.  相似文献   

8.
OBJECTIVE: To evaluate the protective effect of puerarin [an isoflavone compound extracted from Gegen(Radix Puerariae Lobatae)] in scleral remodeling induced by extremely low frequency electromagnetic fields(ELF-EMFs).METHODS: Human fetal scleral fibroblasts(HFSFs)were divided into 5 groups:(a) untreated controls;(b) cells treated with ELF-EMFs;(c) cells treated with ELF-EMFs and puerarin 0.1 μM;(d) cells treated with ELF-EMFs and puerarin 1 μM;(e) cells treated with ELF-EMFs and puerarin 10 μM. Cell proliferation activity was measured by the cell-counting kit-8 assay. Matrix metalloproteinase-2(MMP-2) activity was measured by gelatin enzymography.MMP-2 and collagenⅠ(COL1A1) m RNA, protein expression were measured by Real-Time polymerase chain reaction, Western blot analysis, respectively.RESULTS: Puerarin reduced the inhibition in cell proliferation, MMP-2 activity, m RNA, protein expression of HFSFs exposed to ELF-EMFs and enhanced the COL1A1 m RNA and protein expression.CONCLUSION: Puerarin was found to participate in the matrix remodeling process. It might be a potential agent for the treatment of extracellular matrix degradation of sclera associated with ocular conditions.  相似文献   

9.
OBJECTIVE: To study the effect of puerarin on matrix metalloproteinase-2(MMP-2) gene and protein expression in human fetal scleral fibroblasts(HFSFs) exposed to extremely low frequency electromagnetic fields(ELF-EMF).METHODS: Cultured HFSFs were exposed to 0.2mT ELF-EMF for 24 h. The experimental groups were divided into subgroups treated with 0, 0.1, 1and 10 μM puerarin respectively. The expression of MMP-2 mRNA and protein were detected with real-time polymerase chain reaction and western-blot analysis respectively.RESULTS: MMP-2 mRNA and protein expression increased by 0.793 and 1.130 folds respectively under the exposure of ELF-EMFs at 0.2 mT flux density for24 h. Puerarin at the concentration of 0.1 μM reversed this effect by 8.53% in mRNA and by 17.97%in protein expression(P0.05). The effect was more prominent at higher concentrations(1 and 10 μM,P0.01).CONCLUSION: Exposure to ELF-EMFs increased the expression of MMP-2 mRNA and protein in HFSF cells. Puerarin reversed the action to some extent in a specific concentration range. Our results implied that the puerarin might protect scleral tissue from increased expression induced by exposure to ELF-EMFs.  相似文献   

10.
11.
Objective To study the effect of bentysrepinine(Y101) metabolites on improving binding affinity of HBV DNA polymerase. Methods The binding mode of Y101 and its metabolites with DNA polymerase has been driven by hydrophobic interaction. Results Two compounds, T2 and T4, exhibited the improvement of the binding affinity to HBV DNA polymerase protein, which suggests that the inhibitory activity against HBV DNA polymerase protein can be enhanced. Conclusion The variant docking poses of T2 and T4 might imply the novel recognition of inhibitory effects of T2 and T4, in comparison with Y101.  相似文献   

12.
Bioassay-guided fractionation of an active methyl ethyl ketone extract of Hardwickia binata, using an assay sensitive to DNA polymerase beta inhibition, resulted in the isolation of a potent inhibitor. This proved to be a novel diterpenoid, which has been named harbinatic acid (1). The structure of 1 was established as 3alpha-O-trans-p-coumaroyl-7-labden-15-oic acid from spectroscopic analysis and by comparison with the published data for a structurally related compound. Compound 1 strongly inhibited calf thymus DNA polymerase beta, with an IC(50) value of 2.9 microM.  相似文献   

13.
香港市售蒲公英及其混淆品土公英的DNA指纹鉴别研究   总被引:29,自引:4,他引:29  
采用分子生物技术包括任意引物聚合酶链式反应(AP-PCR)和随意引物扩增的多态性DNA(RAPD)方法扩增蒲公英及其6种土公英混淆品的基因组DNA,获得清晰可靠的DNA指纹图谱。根据琼脂糖凝胶上显示的DNA带型差异可鉴别蒲公英和土公英混淆品。  相似文献   

14.
Crude plant extracts were surveyed for their ability to inhibit DNA polymerase beta. A methyl ethyl ketone extract prepared from Baeckea gunniana was identified as a potent inhibitor of the enzyme. Bioassay-guided fractionation of the extract, using an assay to monitor the inhibitory potential of individual fractions toward DNA polymerase beta, led to the isolation of four active ursane and oleanane triterpenoids (1-4). Inhibitory principle 1 is a new natural product, and 2 is a novel compound. Their structures were established as 3 beta-hydroxyrus-12,19(29)-dien-28-oic acid (1) and 3 beta-hydroxyrus-18,20(30)-dien-28-oic acid (2) by spectroscopic analysis and by comparison with the data for the structurally related compound ursolic acid (4). Also isolated as a DNA polymerase beta inhibitor was oleanolic acid (3). Compounds 1-4 had IC50 values of 5.3-8.5 microM as inhibitors of polymerase beta in the presence of bovine serum albumin (BSA) and 2.5-4.8 microM in the absence of BSA.  相似文献   

15.
To provide some insights how herbal medicines affect deoxyribonucleic acid (DNA) synthesis in the uterus, the DNA polymerase activities (alpha and beta) in uterine samples taken from rats were measured. DNA polymerase alpha activity with respect to DNA content revealed alpha cyclic change with the highest level on proestrus, while DNA polymerase beta activity showed no significant changes during the estrous cycle. The increased period of the activity coincided with that of 17 beta-estradiol (E2) but not progesterone (P4) in the blood. Injection of 10 IU pregnant mare serum gonadotropin (PMS) on day 27 of age gradually increased DNA polymerase alpha activity in uteri, while concomitant treatment with PMS and 200 micrograms Tokishakuyakusan (TS), Keishibukuryogan (KB) or Unkeito (UT) suppressed the enzyme activity, with a most remarkable effect of KB. These results suggest that TS, KB or UT suppresses in vivo DNA polymerase alpha activity induced by PMS in the rat uterus.  相似文献   

16.
17.
以人外周血淋巴细胞非程序DNA合成(UDS)为观察指标,研究了莪术和硫酸镍的遗传毒性效应及莪术对硫酸镍诱导的人外周血淋巴细胞UDS的影响。结果表明,莪术对人外周血淋巴细胞UDS无诱导效应,但当剂量达到1g/ml时,可显著阻抑3H-TdR向细胞DNA的掺入。硫酸镍可大量诱发人外周血淋巴细胞UDS,莪术对硫酸镍和紫外线诱导的人外周血淋巴细胞UDS有明显抑制,且存在剂量效应关系。提示莪术在一定剂量时可明显减轻硫酸镍对人外周血淋巴细胞DNA的损伤,而其本身无致突变作用。但当莪术剂量达到1g/ml时,对DNA的修复合成可造成抑制。  相似文献   

18.
Bioassay-guided fractionation of extracts prepared from Brackenridgea nitida and Bleasdalea bleasdalei, using an assay to detect DNA polymerase beta inhibition, resulted in the isolation of the inhibitory principle, (24E)-3beta-hydroxy-7,24-euphadien-26-oic acid (1), a new euphane triterpenoid. The structure of 1 was established on the basis of HRMS and 1D and 2D NMR spectroscopic methods and was confirmed further by X-ray crystallographic analysis. Compound 1 inhibited rat DNA polymerase beta with an IC(50) value of 23 microM in the presence of bovine serum albumin (BSA) and 9.7 microM in the absence of BSA, consistent with the possibility that 1 may be of utility in vivo. This possibility was further supported by the finding that 1 potentiated the inhibitory action of the anticancer drug bleomycin in cultured P-388D(1) cells, reducing the number of viable cells by 48% when employed at a concentration of 25 microM in the presence of an otherwise nontoxic (75 nM) concentration of bleomycin. Compound 1 is the first euphane-type triterpenoid found to inhibit DNA polymerase beta.  相似文献   

19.
A survey of crude plant extracts for DNA polymerase beta inhibitors resulted in the identification of a methyl ethyl ketone extract prepared from Knema elegans that strongly inhibited the enzyme. Subsequent bioassay-guided fractionation of the extract, using an assay to monitor the activity of DNA polymerase beta, led to the isolation of two potent inhibitors, (+)-myristinins A (1) and D (2), which are known flavans having unusual structures. (+)-Myristinins A and D exhibited IC50 values of 12 and 4.3 microM, respectively, as inhibitors of DNA polymerase beta in the presence of bovine serum albumin (BSA), and 2.7 and 1.2 microM in the absence of BSA. As such, they are the most potent DNA polymerase beta inhibitors reported to date. Compounds 1 and 2 potentiated the cytotoxicity of bleomycin toward cultured P388D1 cells, reducing the number of viable cells by at least 30% when employed at 9 microM concentration for 6 h in the presence of an otherwise nontoxic concentration of bleomycin (75 nM). Principles 1 and 2 also induced strong Cu2+-dependent DNA strand scission in a DNA cleavage assay. Accordingly, 1 and 2 exhibit two activities, namely, DNA polymerase beta inhibition and DNA damage.  相似文献   

20.
Daphne-type diterpenenoids is the major biologically active constituents in the genus Daphne. We find that there are about 101 Daphne-type diterpenes in this genus, most of these compounds show different degrees of inhibitory effect on various cancer cell. Some of them have been studied in depth and the potent molecular mechanisms might be associated with modulation of different cell-signaling pathways. In addition, some compounds of this type also can inhibit the synthesis of protein and DNA. Absolutely, the anti-tumor activity of Daphne-type diterpenes is worthy of attention. Unfortunately, most of the current research on the activity of these compounds is focused on simple drug efficacy, and its in-depth mechanism research is far from enough. On the other point of view, there still exists wide growing space on the depth of these compounds.  相似文献   

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