Steroidal sapogenin contents in some domestic plants

In order to find out the values of the steroid resources for the future use. the compositions and contents of steroidal sapogenins from 13 domestic plants have been investigated. As a result,Dioscorea nipponica, D. quinqueloba andSmilax china were found to have large amount of diosgenin. And pennogenin inTrillium kamtschaticum andParis verticillata, yuccagenin inAllium fistulosum, hecogenin inAgave americana and neochlorogenin inSolanum nigum were appeared to be major steroidal sapogenins.     

薄层层离法在研究天然化合物中的应用 Ⅳ.番麻(Agave americana L.)总甾体皂甙元的鉴定

本文报告了无粘合剂的氧化鋁薄层层离法在甾体皂甙元分离鉴定工作中的实际应用。通过一系列实驗确定:(1)作为吸附剂的氧化鋁应为中性,細度小于140篩孔,活度为Ⅲ或Ⅳ級;(2)不同比例的甲醇-苯作为推进剂,其中(0.5∶99.5)适于分离单經基无酮的甾体皂甙元,(2.5∶97.5)适于分离单羥基无酮及有酮的甾体皂甙元,(5∶95)适于分离双羥基无酮及有酮的甾体皂甙元;(3)适宜的显色剂为25%的磷錮酸醇溶液。应用上述条件对番麻总甾体皂甙元进行薄层层离,得到八个斑点,經用标准品对照,初步鉴定了其中的七个成分。     

Two new prosapogenins from Albizia adianthifolia

Two new triterpenoidal prosapogenins 1 and 2 were obtained from the mild alkaline hydrolysate of the crude saponin fraction of Albizia adianthifolia (Mimosaceae) roots. Their structures were mainly determined by spectral analyses as acacic acid 3-O-beta-D-xylopyranosyl-(1-->2)-beta-D-fucopyranosyl-(1-->6)- 2-acetylamino-2-deoxy-beta-D-glucopyranoside (1) and acacic acid 3-O-(beta-D-xylopyranosyl-(1-->2)-beta-D-fucopyranosyl-(1-->6)- [beta-D-glucopyranosyl-(1-->2)]-beta-D-glucopyranosyl)-21-O-(6(S)-2- hydroxymethyl-6-methyl-6-O-(beta-D-quinovopyranosyl)-2,7-octadienoyl) ester (2). Furthermore, the known julibroside A3 was isolated from the crude saponin mixture. Compounds 1 and 2 did not show any ability to potentiate in vitro cisplatin cytotoxicity in a human colon cancer cell line.     

Degradation of ginseng saponins under mild acidic conditions

Ginseng saponins, ginsenosides Rg (1), Re and Rb (1), decomposed under mild acidic conditions to yield prosapogenins. The structures of the prosapogenins were investigated by (13)C-NMR spectroscopy and Rg (1)-prosapogenin II was shown to be a mixture of ginsenoside Rh (1), and its C-20 epimer, produced by hydrolysis followed by epimerization at C-20. Rg (1)-prosapogenin III, the other prosapogenin derived from ginsenoside Rg (1); was a C-25,26 hydrated derivative of Rg (1)-prosapogenin II. Re-prosapogenin II was identified as a mixture of ginsenoside Rg (2) and its C-20 epimer, and Re-prosapogenine III as a C-25,26 hydrated derivative of Re-prosapogenin II.     

Triterpenoids from the roots ofRubus parvifolius

From the roots ofRubus parvifolius L., four triterpenoidal sapogenins, ursolic acid1, 2α-hydroxyursolic acid2, euscapic acid3, 2α, 3β, 19α-trihydroxyurs-12-en-23,28-dioic acid4 and one triterpenoidal glycoside, suavissimoside R₁ 5, were isolated. The structures were elucidated by spectroscopic methods and chemical transformations. Compound4 was first isolated as free form.     

Triterpenoid prosapogenols and prosapogenins from the husks of Xanthoceras sorbifolia

Two new prosapogenins, 16-O-acetyl-21-O-(4-angeloyl)-α-l-rhamnopyranosyl barringtogenol C (1), 28-O-β-d-glucopyranosyl 16-deoxybarringtogenol C (2), were isolated from the acid hydrolyzate of the crude saponin obtained from the husks of Xanthoceras sorbifolia Bunge, along with six known triterpenoids. These structures were established on the basis of chemical and detailed spectral evidences. Compounds 1 and 2 showed cytotoxic activity against human cell lines (A375-S2, HeLa).     

In vitro cytotoxicity, in vivo biodistribution and antitumor activity of HPMA copolymer–5-fluorouracil conjugates

5-Fluorouracil (5-FU) is an antimetabolite with a broad-spectrum activity against solid tumors. However, its very short half-life in plasma circulation greatly limited the in vivo antitumor efficacy and clinical application. The current work aimed to solve this problem as well as to increase 5-FU biodistribution to tumor by covalently conjugating 5-FU to a biocompatible, non-toxic and non-immunogenic drug carrier – N-(2-hydroxypropyl) methacrylamide (HPMA) copolymer. The in vitro cytotoxicity, in vivo biodistribution and therapeutic efficacy of HPMA copolymer–5-FU conjugates (P-FU) were reported. Cytotoxicity was evaluated by using a serial of tumor cells (A549, CT-26, Hela, HepG₂ cells and 5-FU resistant HepG₂ cells). In vivo biodistribution and therapeutic efficacy were investigated in Kunming mice-bearing hepatoma 22 (H₂₂). Results indicated that P-FU could increase the cytotoxicity of 5-FU in Hela, HepG₂ and 5-FU resistant HepG₂ cells, while it decreases the cytotoxicity of 5-FU in A549 and CT-26. Both in vitro release profile in plasma and biodistribution study showed that P-FU significantly prolonged the drug plasma circulation time. P-FU also showed an over 3-fold larger area under the concentration–time curve (AUC) in tumor when compared with free drug. Therapeutic evaluation also demonstrated that the treatment with P-FU displayed stronger inhibition of the tumor growth when compared with that of control group (physiologic saline) or 5-FU group at the same dose. All the results suggested that P-FU could increase cytotoxicity of 5-FU in certain cancer cell lines, prolong 5-FU circulation time in vivo, enhance 5-FU distribution to tumor and improve therapeutic efficacy. Therefore, HPMA copolymer is a potential carrier for 5-FU for the effective treatment of cancer.     

狭叶香茶菜二萜成分的研究

A spirosecokaurenoid, angustifolin (Ⅰ) was isolated from the leaves of Rabdosia angustifolia (Dunn) Hara (Labiatae) and its structure was established from spectral and chemical evidence. One known diterpenoid, isodonal (V) was also isolated together with β-sitosterol. (Ⅰ) and (Ⅴ) showed in vitro cytotoxicity and in vivo tumor inhibitory activities.     

Constitutents and the antitumor principle ofAllium victorialis var.platyphyllum

To search for cytotoxic components from Allium victorialis, MTT assays on each extract and an isolated component, gitogenin 3-O-lycotetroside, were performed against cancer cell lines. Cytotoxicities of most extract were shown to be comparatively weak, though IC50 values of CHCl3 fraction was found to be <31.3-368.4 microg/ml. From the incubated methanol extract at 36 degrees C, eleven kinds of organosulfuric flavours were predictable by GC-MS performance. The most abundant peak was revealed to be 2-vinyl-4H-1,3-dithiin (1) by its mass spectrum. Further, this extract showed significant cytotoxicities toward cancer cell lies. Silica gel column chromatography of the n-butanol fraction led to the isolation of gitogenin 3-O-lycotetroside (3) along with astragalin (4) and kaempferol 3, 4'-di-O-beta-D-glucoside (5). This steroidal saponin exhibited significant cytotoxic activities (IC50, 6.51-36.5 microg/ml) over several cancer cell lines. When compound 3 was incubated for 24 h with human intestinal bacteria, a major metabolite was produced and then isolated by silica gel column chromatography. By examining parent- and prominent ion peak in FAB-MS spectrum of the metabolite, the structure was speculated not to be any of prosapogenins of 3, suggesting that spiroketal ring were labile to the bacterial reaction. These suggest that disulfides produced secondarily are the antitumor principles.     

甘草配伍大戟的体外肝毒性研究

目的 研究甘草和大戟配伍的体外肝毒性。方法 采用显微观察法和MTT法检测不同浓度的甘草单煎液、大戟单煎液、甘草-大戟合煎液和甘草-大戟单煎混合液对人肝癌细胞HepG2增殖的影响,并比较大戟单煎液、甘草-大戟合煎液和甘草-大戟单煎混合液相当浓度下细胞毒性的大小。结果 大戟单用及大戟与甘草配伍均有细胞毒性,且呈剂量相关性;与大戟单煎液相比,甘草-大戟单煎混合液细胞毒性无明显差异,甘草-大戟合煎液细胞毒性减小。结论 甘草和大戟配伍导致大戟的体外肝毒性减小。     

商陆多糖Ⅰ联合白细胞介素2对小鼠脾细胞杀瘤活性的影响

商陆多糖Ⅰ(PAP-I),0.3～3μg·ml^-1和小鼠脾细胞培养3～5d可显著增强其杀伤P815肿瘤细胞活性及IL-2(250～500IU·ml^-1)诱导的LAK细胞活性,最适浓度为1μg·ml^-1。PAP-I及IL-2和脾细胞培养的上清液对P815肿瘤细胞无细胞毒作用,但能增强脾细胞及LAK细胞杀瘤活性。PAP-I,5,10及50mg·kg-1,ip可增强脾细胞杀伤P₈₁₅和L₉₂₉细胞的活性及IL-2诱导的LAK细胞活性。     

Cytotoxic saponins from Schefflera fagueti

Six new lupane (1 - 4) and oleanane saponins (5 and 6) were isolated from the aerial parts of Schefflera fagueti Baill. (Araliaceae). Their structures were determined by 2D-NMR spectroscopy (DQF-COSY, 1D-TOCSY, 2D-HOHAHA, 1D-ROESY, HSQC, HMBC). The antiproliferative activity of compounds 1 - 6 and of their prosapogenins (1a - 6a) was evaluated using three continuous murine and human culture cell lines J774, HEK-293, WEHI-164. Oleanane saponins 5 and 6 were the most active, showing significant inhibitory effects on all cell lines, while their prosapogenins 5a and 6a demonstrated minor activity.     

几种国产植物中甾体皂素成分的研究(Ⅱ)

前报从国产植物丝兰Yucca fiamentosa L.中分离出三种成份,其中二种已经鑑定为5,10-反式-3β-羥基螺甾(Tigogenin)及5,10-反式-2α,3β-双羥基螺甾(Gitogenin)。第三种成份今证明为5,10-反式-3β基-12-酮螺甾(Hecogenin)。另外从植物番麻Agaveamericana L.中提出約含0.15%的皂素混合物,内約含九份5,10-反式-3β-羥基-12-酮螺甾(Hecogenin),一份5,10-反式-3β,6β-双羥基螺甾(Chlorogenin),此外又从国药知母Anemarrhena asphodeloides Bunge中提出含量約0.5%的5,10-顺式-3β-羥基螺甾(Sar-sasapogenin)。     

Cross-linked Small Polyethylenimines: While Still Nontoxic,Deliver DNA Efficiently to Mammalian Cells <Emphasis Type="Italic">in Vitro</Emphasis> and <Emphasis Type="Italic">in Vivo</Emphasis>

No HeadingPurpose. Polyethylenimine (PEI) is among the most efficient nonviral gene delivery vectors. Its efficiency and cytotoxicity depend on molecular weight, with the 25-kDa PEI being most efficient but cytotoxic. Smaller PEIs are noncytotoxic but less efficient. Enhancement in gene delivery efficiency with minimal cytotoxicity by cross-linking of small PEIs via potentially biodegradable linkages was explored herein. The hypothesis was that cross-linking would raise the polycations effective molecular weight and hence the transfection efficiency, while biodegradable linkages would undergo the intracellular breakdown after DNA delivery and hence not lead to cytotoxicity. Toward this goal, we carried out cross-linking of branched 2-kDa PEI and its 1:1 (w/w) mixture with a linear 423-Da PEI via ester- and/or amide-bearing linkages; the in vitro and in vivo gene delivery efficiency, as well as toxicity to mammalian cells, of the resultant cross-linked polycations were investigated.Methods. The efficiency of the cross-linked PEIs in delivering in vitro a plasmid containing -galactosidase gene and their cytotoxicity were investigated in monkey kidney cells (COS-7). Dynamic light scattering was used to compare the relative DNA condensation efficiency of the unmodified and cross-linked PEIs. In vivo gene delivery efficiency was evaluated by intratracheal delivery in mice of the complexes of a luciferase-encoding plasmid and the PEIs and estimating the luciferase expression in the lungs.Results. Cross-linking boosted the gene delivery efficiency of the small PEIs by 40- to 550-fold in vitro; the efficiency of the most potent conjugates even exceeded by an order of magnitude that of the branched 25-kDa PEI. Effective condensation of DNA was evident from the fact that the mean diameter of the complexes of the cross-linked PEIs was some 300 nm with a narrow size distribution, while the complexes of the unmodified small PEIs exhibited a mean size of >700 nm with a very broad size distribution. At concentrations where the 25-kDa PEI resulted in >95% cell death, the conjugates afforded nearly full cell viability. The cross-linked PEIs were 17 to 80 times m ore efficient than the unmodified ones in vivo; furthermore, their efficiencies were up to twice that of the 25-kDa PEI.Conclusions. Cross-linking of small PEIs with judiciously designed amide- and ester-bearing linkers boosts their gene delivery efficiency both in vitro and in vivo without increasing the cytotoxicity. The high efficiency is dependent on the nature of the linkages and the PEIs used.     

Mollugin induces apoptosis in human Jurkat T cells through endoplasmic reticulum stress-mediated activation of JNK and caspase-12 and subsequent activation of mitochondria-dependent caspase cascade regulated by Bcl-xL

Exposure of Jurkat T cells to mollugin (15–30 μM), purified from the roots of Rubia cordifolia L., caused cytotoxicity and apoptotic DNA fragmentation along with mitochondrial membrane potential disruption, mitochondrial cytochrome c release, phosphorylation of c-Jun N-terminal kinase (JNK), activation of caspase-12, -9, -7, -3, and -8, cleavage of FLIP and Bid, and PARP degradation, without accompanying necrosis. While these mollugin-induced cytotoxicity and apoptotic events including activation of caspase-8 and mitochondria-dependent activation of caspase cascade were completely prevented by overexpression of Bcl-xL, the activation of JNK and caspase-12 was prevented to much lesser extent. Pretreatment of the cells with the pan-caspase inhibitor (z-VAD-fmk), the caspase-9 inhibitor (z-LEHD-fmk), the caspase-3 inhibitor (z-DEVD-fmk) or the caspase-12 inhibitor (z-ATAD-fmk) at the minimal concentration to prevent mollugin-induced apoptosis appeared to completely block the activation of caspase-7 and -8, and PARP degradation, but failed to block the activation of caspase-9 and -3 with allowing a slight enhancement in the level of JNK phosphorylation. Both FADD-positive wild-type Jurkat clone A3 and FADD-deficient Jurkat clone I2.1 exhibited a similar susceptibility to the cytotoxicity of mollugin, excluding involvement of Fas/FasL system in triggering mollugin-induced apoptosis. Normal peripheral T cells were more refractory to the cytotoxicity of mollugin than were Jurkat T cells. These results demonstrated that mollugin-induced cytotoxicity in Jurkat T cells was mainly attributable to apoptosis provoked via endoplasmic reticulum (ER) stress-mediated activation of JNK and caspase-12, and subsequent mitochondria-dependent activation of caspase-9 and -3, leading to activation of caspase-7 and -8, which could be regulated by Bcl-xL.     

Structural and pharmacological characterization of the crotamine isoforms III-4 (MYX4_CROCu) and III-7 (MYX7_CROCu) isolated from the Crotalus durissus cumanensis venom

Two major crotamine isoforms (III-4 and III-7) were obtained combining two chromatographic steps on molecular exclusion chromatography (Sephadex G-75) and ion-exchange column (Protein Pack SP 5PW) of the rattlesnake Crotalus durissus cumanensis venom. The “in vivo” myotoxic effect of the venom, its “in vitro” cytotoxicity in myoblasts and myotubes (C2C12) and the neurotoxic and edema-forming activity were characterized. The molecular masses of the crotamine isoforms were 4907.94 Da (III-4) and 4985.02 Da (III-7) and, as determined by mass spectrometry, both contained six Cys residues. Enzymatic hydrolysis followed by de novo sequencing through tandem mass spectrometry was used to determine the primary structure of both isoforms. III-4 and III-7 isoforms presented a 42-amino acid residues sequence and showed high molecular amino acid sequence identity with other crotamine-like proteins from Crotalus durissus terrificus. In vivo, both crotamine isoforms induced myotoxicty and a systemic interleukin-6 response upon intramuscular injection. These new crotamine isoforms induced low cytotoxicity in skeletal muscle myoblasts and myotubes (C2C12) and both induced a facilitatory effect on neuromuscular transmission in young chick biventer cervicis preparation. Edema-forming activity was also analyzed by injection of the crotamine isoforms into the right paw, since both crotamine isoforms exert a strong pro-inflammatory effect.     

dl-扁桃酸对人精子与阴道黏膜上皮VK2/E6E7细胞的毒性研究

目的探讨dl-扁桃酸对人阴道黏膜上皮细胞(VK2/E6E7)与精子的细胞毒性损伤。方法不同浓度的dl-扁桃酸处理高活力精子20 s,计算机辅助精子分析仪测定精子活率,扫描电子显微镜检测精子受损情况。1.25,2.5 g·L?1 dl-扁桃酸和4.0 g·L?1壬苯醇醚(nonoxynol-9,N-9)处理VK2/E6E7细胞,MTT法检测细胞活性,ELISA试剂盒检测乳酸脱氢酶(LDH)释放率,并用流式细胞法检测细胞凋亡率。结果 dl-扁桃酸抑制精子活率的半数有效浓度约为1.25 g·L?1,最低有效浓度约为2.5 g·L?1。扫描电镜结果显示,dl-扁桃酸处理组精子表面结构与对照组形态相似,无明显受损特征,N-9组精子严重受损。MTT实验结果表明,1.25 g·L?1 dl-扁桃酸组细胞存活率>95%,2.5 g·L?1 dl-扁桃酸组细胞存活率约为50%。1.25,2.5 g·L?1 dl-扁桃酸处理组LDH释放量只有微量检出,远低于N-9组。流式细胞检测表明,1.25,2.5 g·L?1 dl-扁桃酸处理组中活细胞和晚期凋亡比例与对照组相近,早期凋亡细胞略少于对照组,死亡细胞稍多于对照组,N-9组大量细胞死亡。结论 dl-扁桃酸对VK2/E6E7细胞毒性远低于N-9,其对精子的抑制作用不是通过破坏精子质膜与鞭毛来实现。     

Lyophilized Paclitaxel Magnetoliposomes as a Potential Drug Delivery System for Breast Carcinoma via Parenteral Administration: <Emphasis Type="Italic">In Vitro</Emphasis> and <Emphasis Type="Italic">in Vivo</Emphasis> Studies

No HeadingPurpose. The study reports in vitro and biological evaluation of lyophilized negatively charged paclitaxel magnetic liposomes as a potential carrier for breast carcinoma via parenteral administration.Methods. Paclitaxel in magnetoliposomes were extracted by centrifugation and quantified by high-performance liquid chromatography (HPLC). Biological properties were studied using pharmacokinetics, in vivo distribution and cytotoxicity assays, as well as a mouse model of EMT-6 breast cancer.Methods. Pharmacokinetic studies showed that encapsulation of paclitaxel in magnetoliposomes produced marked difference over the drug in Cremophor EL/ethanol pharmacokinetics, with an increased t_1/2 19.37 h against 4.11 h. For in vivo distribution, paclitaxel concentration of lyophilized magnetoliposomes in the tumor was much higher than that of lyophilized conventional liposomes or Cremophor EL/ethanol, whereas in heart it was much lower than the latter two formulations via s.c. and i.v. administration. Lyophilized paclitaxel magnetic liposomes showed more potency on the therapy of breast cancer than other formulations via s.c. and i.p. administration.Conclusions. The current study demonstrates that paclitaxel magnetoliposomes can effectively be delivered to tumor and exert a significant anticancer activity with fewer side effects in the xenograft model.     

Glossogin, a novel phenylpropanoid from Glossogyne tenuifolia, induced apoptosis in A549 lung cancer cells

Glossogyne tenuifolia has been shown to exhibit good antioxidant and anticancer activity. In this study, a new phenylpropanoid compound, glossogin (1′-acetoxy-4-O-isovalyryleugenol), was isolated from ethyl acetate extract of G. tenuifolia by using column chromatography and HPLC. Its chemical structure was determined by ¹H and ¹³C NMR, MS and IR spectroscopic evidence. This compound showed the cytotoxicity against A549 human lung cancer cell line and it induced the progressing apoptosis on A549 cells. This apoptosis was verified as A549 cells were arrested at the sub-G₁ phase. The apoptosis was accompanied by release of cytochrome C and activation of caspase-9 and -3. It was also associated with the decrease in Bcl-2 and Bcl-xL protein levels, and the increase in Bad protein expression. Data analysis suggests glossogin exerted significant apoptotic effect on A549 cells through the mitochondrial pathway. Hence, our findings showed that glossogin exhibited potential anticancer activity against lung cancer through proliferating inhibition and apoptosis induction of cancer cells.