缺氧调控人趋化因子受体CCR5启动子区的表达分析

目的:分析人趋化因子受体5(CCR5)基因启动子区序列在缺氧条件下的表达.方法:构建CCR5基因启动子区萤光素酶报告基因载体,转染入MDA-MB-435细胞中,检测分析其双萤光素酶活性.结果:CCR5基因启动子区的pGL3重组质粒在缺氧条件下的MDA-MB-435细胞中能表现出明显的萤光素酶海性.结论:CCR5基因启动区序列中存在缺氧诱导CCR5基因转录的主要上调元件.     

10-Methoxydihydrofuscin,fuscinarin, and fuscin,novel antagonists of the human CCR5 receptor from Oidiodendron griseum

Two new compounds, 10-methoxydihydrofuscin (1) and fuscinarin (2), and one known compound, fuscin (3), have been isolated from the soil fungus Oidiodendron griseum. These compounds were found to compete effectively with macrophage inflammatory protein (MIP)-1 alpha for binding to human CCR5, an important anti HIV-1 target that interferes with HIV entry into cells. The structures of these compounds were elucidated by spectroscopic methods.     

Inhibition of the human chemokine receptor CCR5 by variecolin and variecolol and isolation of four new variecolin analogues, emericolins A-D, from Emericella aurantiobrunnea

An extract from the fungus Emericella aurantiobrunnea was found to compete with macrophage inflammatory protein (MIP)-1alpha for binding to human CCR5 in a scintillation proximity assay (SPA). Bioassay-guided fractionation led to the isolation of variecolin (1) and variecolol (2), which had IC50 values of 9 and 32 microM, respectively. An X-ray crystal structure of variecolin (1) was obtained for the first time. Also isolated were four new inactive analogues, emericolin A (3), B (4), C (5), and D (6), and the relative stereochemistry of these compounds was determined by NMR methods using ROESY spectra and 1H/1H coupling constants.     

Isolation and structure elucidation of the new fungal metabolite (-)-xylariamide A

Chemical investigations of the terrestrial microfungus Xylaria sp. have afforded the new natural product (-)-xylariamide A (1). The gross structure of 1 was determined by interpretation of 1D and 2D NMR, UV, IR, and MS data. Confirmation of the structure and the absolute stereochemistry of 1 were determined by the total synthesis of (+)-xylariamide A (2). Synthetic 2 was produced by N,O-bis(trimethylsilyl)acetamide-induced coupling of 3-chloro-L-tyrosine (3) with (E)-but-2-enedioic acid 2,5-dioxo-pyrrolidin-1-yl ester methyl ester (4). Optical rotation comparison of 1 with 2 indicated that the natural product (1) contained 3-chloro-D-tyrosine. Both enantiomers of xylariamide A were tested in a brine shrimp lethality assay, and only the natural product (1) showed toxicity.     

Isolation and structure of palstatin from the Amazon tree Hymeneae palustris(1)

Bioassay (P388 lymphocytic leukemia cell line and human cancer cell lines) guided separation of an extract prepared from the leaves of Hymenaea palustris Ducké led to the isolation of six cancer cell growth inhibitory flavonoids (1-6). The structures were elucidated by HRMS and 1D and 2D NMR spectral analysis. The new flavonolignan 1 designated palstatin proved to be a methoxy structural modification of 5'-methoxyhydnocarpin-D (2). Flavones 1-4 inhibited growth of the pathogenic bacteria Enterococcus faecalis and/or Neisseria gonorrhoeae.     

Isolation and structure (X-ray analysis) of ent-norsecurinine, an alkaloid from Phyllanthus niruri

The isolation and structure determination of the alkaloid ent-norsecurinine (4) from Phyllanthus niruri L. is described. The structure and absolute stereochemistry have been confirmed by an X-ray analysis of ent-norsecurinine hydrochloride.     

脑卒中与血小板活化因子及其受体拮抗剂

脑卒中是一种急性脑血管疾病,具有发病率高、致残率和致死率高的特点。全球脑卒中防治形势严峻,抗血小板聚集治疗能够有效防治脑卒中。血小板活化因子(PAF)是介导血小板聚集的另一重要介质,在脑卒中病理过程中起着重要作用。近年来,PAF受体拮抗剂在脑卒中防治领域逐渐引起国际关注。该文对PAF受体拮抗剂的分类、作用机制及药物特征进行综述,以期对临床用药及新药研发提供有价值的指导和方向。     

电针对偏头痛大鼠5-HT_(1D)受体表达的调控作用研究

目的研究电针对偏头痛大鼠5-HT_(1D)受体的调控作用,探索电针治疗偏头痛的作用机制。方法成年雄性SD大鼠50只,随机分为5组:对照组(C组),模型组(M组),单穴组(风池)(EA1组),配穴组(风池+阳陵泉)(EA2组),非穴组(NA组)。C组只予以电极安置手术,其余各组在电刺激后予以相应电针治疗。电子von Frey测量大鼠头面部机械痛阈(第0、2、4、6天);实时荧光定量PCR和western blot对偏头痛大鼠三叉神经节(TG)与三叉神经脊束核尾侧亚核(TNC)的5-HT_(1D)受体表达进行检测。结果在第0天,各组大鼠机械痛阈组间差异无统计学意义;在第2、4和6天,M组大鼠机械痛阈显著低于C组(P<0.001),EA1组和EA2组分别与C组比较差异无统计学意义,NA组与M组差异无统计学意义。M组5-HT_(1D)受体表达显著降低(P<0.001),EA1组与EA2组的5-HT_(1D)受体表达显著高于M组(P<0.001),NA组与M组差异无统计学意义,EA2组的5-HT_(1D)受体表达高于EA1组(P<0.05)。结论电针对偏头痛大鼠TG与TNC部位的5-HT_(1D)受体表达起到上调作用,可能是针刺治疗偏头痛的机制之一。     

Isolation and structure of ruprechstyril from Ruprechtia tangarana

Bioassay (P388 lymphocytic leukemia cell line and human cancer cell lines)-guided separation of an extract prepared from the stem bark and twigs of the previously uninvestigated Ruprechtia tangarana led to the isolation of a new isocarbostyril designated ruprechstyril (1), secalonic acid A (2), 2'-O-methylevernic acid (3), 3,3',4-tri-O-methylflavellagic acid (4), lichexanthone (5), methyl asterrate (6), and 3beta,22E,24S-stigmasta-5,22-dien-3-ol (7). Only secalonic acid A exhibited cancer cell and microbial growth inhibition. The structure of ruprechstyril (1) was determined by HRMS and 1D and 2D NMR spectra and confirmed by single-crystal X-ray analysis. The structures and absolute stereochemistry of five of the other compounds were also established by X-ray crystal structure determination.     

苦碟子中黄酮苷的分离与结构鉴定

苦碟子为菊科植物抱茎苦荬菜[Ixeris sonchifolia(Bge.)Hance]的当年生干燥全草.具有清热解毒,消肿止痛之功效.我们采用MS,NMR方法对该植物中首次分离得到的新黄酮苷化合物进行了研究.     

Plant antimutagenic agents, 5. Isolation and structure of two new isoflavones, fremontin and fremontone from Psorothamnus fremontii

Two new isoflavones, fremontin and fremontone, were isolated from roots of Psorothamnus fremontii (Fabaceae), a desert plant. Compound 1 has the structure 5'-(alpha, alpha-dimethylallyl)-5,7,2',4'-tetrahydroxyisoflavone; compound 2 is similar but also contains the 3'-(gamma,gamma-dimethylallyl) substituent. The alpha,alpha-dimethylallyl substituent is rarely observed, and the combination of the alpha,alpha- and gamma,gamma-dimethylallyl substituents is unprecedented. Both 1 and 2 were nontoxic toward Salmonella typhimurium and were both highly active in the inhibition of mutagenicity of ethyl methanesulfonate (EMS) at all concentrations tested. Compound 2 was more active than 1 in the inhibition of mutagenicity of 2-aminoanthracene (2AN) and acetylaminofluorene (AAF) toward S. typhimurium.     

毛叶假鹰爪根化学成分的研究

从毛叶假鹰爪Desmosdumosus（Roxb．）Saff.根中分离得到12个化合物，经理化性质和波谱分析鉴定了其中7个化合物，分别是lawinal（Ⅰ），5，7-二羟基-8-甲酰基-6-甲基双氢黄酮（Ⅱ），去甲氧杜鹃花素（Ⅲ），去甲氧杜鹃花素-7-甲酸（Ⅳ），β-谷甾醇（Ⅴ），豆甾醇（Ⅶ）和苯甲酸（Ⅷ）。化合物Ⅱ为天然界首次分得，Ⅲ，Ⅳ，Ⅵ为本种植物中首次分得。     

霞草中三萜化合物的分离与结构鉴定

目的为开发利用霞草Gyp soph ila oldham iana根部资源,并从中寻找新的天然活性成分。方法利用多种柱色谱技术进行分离纯化,根据理化性质和现代波谱技术并辅以化学方法进行结构鉴定。结果从霞草根部甲醇提取物的正丁醇部分和醋酸乙酯部分分得3个五环三萜化合物,分别鉴定为:齐墩果酸(o leano lic ac id,Ⅰ)、co llinsogen in(Ⅱ)、3-O--βD-xy lopyranosy l-(1→3)-[-βD-ga lactopyranosy l-(1→2)]--βD-g lucuronopyranosy l gypso-gen in(Ⅲ)。结论化合物Ⅲ为新化合物,命名为霞草苷Ⅰ(o ldham ianos ideⅠ);化合物Ⅰ和Ⅱ均为首次从该植物中分得。     

Isolation and structure of the cytotoxic cycloheptapeptide phakellistatin 13

A new cyclic heptapeptide phakellistatin 13 (1) had been isolated from the sponge Phakellia fusca Thiele, collected at Yongxing Island of China. Its structure was elucidated as cyclo-(Pro1-Trp-Leu-Thr-Pro2-Gly-Phe) on the basis of MS, UV, IR, and high-field NMR (600 MHz) analysis. The compound was significantly cytotoxic against the human hepatoma BEL-7404 cell line with an ED(50) < 10(-2) microg/mL.     

The saponin DT-13 inhibits gastric cancer cell migration through down-regulation of CCR5-CCL5 axis

AIM： To investigate the effect of DT-13 on gastric cancer cell migration, and to explore the possible mechanisms underlying the anti-metastasis activity of DT-13. METHODS： Growth inhibition of DT-13 was analyzed by the MTT assay. Cell migration was measured by the scratch-wound assay and transwell double chamber assay. To investigate the possible mechanisms underlying the anti-metastasis activity of DT-13, chemokine receptors that are involved in cancer metastasis（CCR2, CCR5, CCR7, CXCR4, and CXCR6） were detected by conventional PCR. The effect of DT-13 on CCR5 and CXCR4 expression was further evaluated by quantitative PCR and Western blot, respectively. The secretion of CCL5（ligand of CCR5） and SDF-1（ligand of CXCR4） were detected by enzyme-linked immunosorbent assay（ELISA）. RESULTS： DT-13 inhibited BGC-823 and HGC-27 cell growth in a dose dependent manner, and the estimated IC50 value for 24 h treatment was 23.5 ± 5.1 μmol·L^-1 for BGC-823 cells and 35.6 ± 7.6 μmol·L^-1 for HGC-27 cells. DT-13 also significantly decreased gastric cancer cell migration. DT-13 significantly decreased the gene expression of CCR5 in both BGC-823 and HGC-27 gastric cancer cells, and moderately reduced the expression of CXCR4. Similar to the results of gene expression, significant down-regulation of CCR5 protein was observed, but CXCR4 protein levels were much less affected. CCL5 secretion, but not SDF-1 production, was inhibited by DT-13. CONCLUSION： DT-13 inhibited gastric cancer cell migration by down-regulation of the CCR5-CCL5 axis.     

Identification and characterization of saikosaponins as antagonists of transient receptor potential A1 channel

Neuropathic pain is associated with an increased sensitivity to painful stimuli or abnormal sensitivity to otherwise innocuous stimuli. However, in addition to adverse effects, currently available drugs have shown limited response in patients with neuropathic pain, which provides a rationale to explore new drug classes acting on novel targets and with better efficacy and safety profiles. Here, we found that saikosaponins potently inhibit agonist‐induced activation of the transient receptor potential A1 (TRPA1) channel, which has been reported to mediate neuropathic pain by sensing a variety of chemical irritants. Molecular docking and site‐directed mutagenesis analyses suggested that saikosaponins bind to the hydrophobic pocket in TRPA1 near the Asn855 residue, which, when mutated to Ser, was previously associated with enhanced pain perception in humans. In support of these findings, saikosaponin D significantly attenuated agonist‐induced nociceptive responses and vincristine‐induced mechanical hypersensitivity in mice. These results indicate that saikosaponins are TRPA1 antagonists and provide a basis for further elaboration of saikosaponin derivatives for the development of new therapeutics for neuropathic pain.     

萱草根化学成分的分离与结构鉴定(Ⅱ)

目的研究萱草Hemerocallis fulva根的化学成分。方法用色谱方法进行分离纯化萱草根的氯仿和正丁醇提取物,根据化合物的理化性质和光谱数据进行结构鉴定。结果从萱草根的氯仿和正丁醇提取物中分离鉴定了10个化合物:蒺藜嗪(terresoxazine,Ⅰ)、11-氧代-β-乳香酸(Ⅱ)、何伯烷-6α,22-二醇(Ⅲ)、海可皂苷元(Ⅳ)、谷甾-4-烯-3β-醇(Ⅴ)、谷甾-4-烯-3-酮(Ⅵ)、ω-阿魏酰氧酸(ω-feruloyloxy acid,Ⅶ)、3,4-二羟基反式肉桂酸(Ⅷ)、对甲基反式肉桂酸(Ⅸ)、香草酸(Ⅹ)。结论化合物Ⅰ～Ⅳ、Ⅶ为首次从该属植物中分得。     

Antineoplastic agents 430. Isolation and structure of cribrostatins 3, 4, and 5 from the republic of maldives cribrochalina species

Continued investigation of cancer-cell growth-inhibitory constituents of the blue marine sponge Cribrochalina sp. has led to discovery of cribrostatins 3 (4a), 4 (5), and 5 (4b) in 10(-5) to 10(-7) % of the wet weight. The structure of cribrostatin 3 (4a) was determined by results of high field (500 MHz) (1)H and (13)C NMR and HRMS interpretations. The same general approach to the structures of cribrostatins 4 (5) and 5 (4b) was completed by X-ray crystal structure determinations. Cribrostatins 3, 4, and 5 provided significant cancer cell line inhibitory activities. Cribrostatins 1 and 2(2) and the newly isolated cribrostatins 3-5 displayed antibacterial and/or antifungal activities.