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31.
目的:探讨重楼皂苷VII (Paris saponin VII, PSVII) 对人结肠癌SW480 细胞凋亡和周期的影响及其机制。方法:采用Cell Counting Kit-8(CCk-8)试剂盒方法观察PSVII 对SW-480 细胞增殖的影响;流失细胞术研究PSVII对SW480细胞凋亡和周期的 作用;培养SW-480 细胞并给予1.0 umol/L、2.0 umol/L 和4.0 umol/L PSVII 24 h后,采用Western blot 法检测凋亡相关蛋白 Caspase-3、Caspase-8、Caspase-9、Bax和Bcl-2 及周期相关蛋白Cdk-4、Cdk-6、CyclinD1 和p21 的表达变化。结果:PSVII可明显抑 制SW-480 细胞增殖,并诱导其凋亡,其IC50值为5.25± 0.46 umol/L;PSVII 可促进SW-480 细胞Caspase-3、Caspase-8、Caspase-9、 Bax及p21 的表达,降低Bcl-2、Cdk-4、Cdk-6和CyclinD1 的表达。结论:PSVII可以通过线粒体和死亡受体途径诱导SW-480 细胞 凋亡;将SW-480 细胞周期阻滞于G1 期是通过上调p21,抑制Cdk-4、Cdk-6 与Cyclin D1 周期调控蛋白的表达。  相似文献   
32.
Cancer is a multi‐faceted disease comprised of a combination of genetic, epigenetic, metabolic and signalling aberrations which severely disrupt the normal homoeostasis of cell growth and death. Rational developments of highly selective drugs which specifically block only one of the signalling pathways have been associated with limited therapeutic success. Multi‐targeted prevention of cancer has emerged as a new paradigm for effective anti‐cancer treatment. Platycodin D, a triterpenoid saponin, is one the major active components of the roots of Platycodon grandiflorum and possesses multiple biological and pharmacological properties including, anti‐nociceptive, anti‐atherosclerosis, antiviral, anti‐inflammatory, anti‐obesity, immunoregulatory, hepatoprotective and anti‐tumour activities. Recently, the anti‐cancer activity of platycodin D has been extensively studied. The purpose of this review was to give our perspectives on the current status of platycodin D and discuss its anti‐cancer activity and molecular mechanisms which may help the further design and conduct of pre‐clinical and clinical trials to develop it successfully into a potential lead drug for oncological therapy. Platycodin D has been shown to fight cancer by inducing apoptosis, cell cycle arrest, and autophagy and inhibiting angiogenesis, invasion and metastasis by targeting multiple signalling pathways which are frequently deregulated in cancers suggesting that this multi‐target activity rather than a single effect may play an important role in developing platycodin D into potential anti‐cancer drug.  相似文献   
33.
从石竹科植物多荚草(Polycarpon prostratum(Forssk.)Aschers.et Schwein.ex Aschers)中分离得到3个新的柴胡皂甙类化合物:prostratoside A ̄C(1 ̄3)。它们的结构通过波谱方法分别鉴定为:3-O-{β-D-xylopyranosyl-(1→2)-β-D-glucopyranosyl-(1→4)-「β-D-glucopyranosy  相似文献   
34.
Summary Callus culture was initiated from expiants of mature root tissues of ginseng (Panax ginseng C.A. Meyer) on MS medium enriched with 2,4-D. The ageing callus produced numerous embryoids in this medium. Reculture of these embryoids in media (1/2 MS or B5) supplemented with benzyladenine and gibberellic acid resulted in profuse plantlet regeneration.  相似文献   
35.
Endophytic fungi play important roles for host's stress tolerance including invasion by pathogenic microbes. Small molecules are common weapons in the microbe–microbe interactions. Panax notoginseng is a widely used traditional Chinese medicinal plant and harbors many endophytes, some exert functions against pathogens. Here, we report six new compounds named myrothins A–F ( 1 – 6 ) produced by Myrothecium sp. BS-31, an endophyte isolated from P. notoginseng, and their antifungal activities against pathogenic fungi causing host root-rot disease. Their structures were elucidated with analysis of spectroscopic data including 1D and 2D NMR, HR-ESI-MS. Myrothins B ( 2 ) and E ( 5 ) showed the weak activity against Fusarium oxysporum and Phoma herbarum, and myrothins F ( 6 ) showed weak activity against F. oxysporum.  相似文献   
36.
秦岭产珠子参叶的达玛烷型皂甙研究(1)   总被引:10,自引:0,他引:10  
从陕西省秦岭产珠子参(Panax japonicus C.A.Meyer var.major(Burk.)Wu etFeng)的叶中分离到十个新的达玛烷型四环三萜皂甙,经光谱测定和化学降解,其中四个的化学结构分别为珠子参甙(majoroside)F_1(1)、F_2(2)、F_3(3)和F_4(4)。同时,还分离到已知的人参甙(ginsenoside)Rd(5)、Re(6)、Rg_1(7)、Rg_2(8)和F_2(9)。  相似文献   
37.
The most abundant root proteins of ginseng (Panax ginseng) have been detected and identified by comparative proteome analysis with cultured hairy root of ginseng. Four abundant proteins (28, 26, 21 and 20 kDa) of P. ginseng had isoforms with different pl values on two-dimensional gel electrophoresis (2DE). The results of N-terminal and internal amino acid sequencing, however, showed that all of them originate from a 28 kDa protein, known as ginseng major protein (GMP). The GMP gene was searched for in the expressed sequence tag database of P. ginseng and found to encode a 27.3 kDa protein having 238 amino acid residues. Analysis of the amino acid sequences indicates that GMP exhibits high sequence homology with plant RNases and RNase-like proteins. However, purified GMP had no RNase activity even though it has conserved amino acid residues known to be essential for active sites of RNase. The GMPs present in ginseng main root were not expressed in cultured hairy roots of ginseng. 2DE analysis showed that the amounts of GMPs in main roots change according to seasonal fluctuation. These results suggest that the GMPs are root-specific RNase-like proteins, which function as vegetative storage proteins of ginseng for survival in the natural environment.  相似文献   
38.
盾叶薯蓣地上部分的三个新甾体皂甙   总被引:11,自引:0,他引:11  
从盾叶薯蓣Dioscorea zingiberensis Wright地上部分分离鉴定了四个甾体皂甙,经鉴定甙A为约莫皂甙元-3-O-[α-L-鼠李吡喃糖基(1→2)]-β-D-葡萄吡喃糖甙;甙B为24α-羟基约莫皂甙元-3-O-[α-L-鼠李吡喃糖基(1→2)]β-D-葡萄吡喃糖甙;甙C为约莫皂甙元-3-O-[α-L-鼠李吡喃糖基(1→2)][β-D-葡萄吡喃糖基(1→4)]-β-D-葡萄吡喃糖基;甙D为约莫皂甙元-3-O-[α-L-鼠李吡喃糖基(1→2)][β-D-葡萄吡喃糖基(1→3)]-β-D-葡萄吡喃糖甙。前三者为新化合物,分别命名为盾叶皂甙A_1、A_2、A_3(zingiberoside A_1、A_2、A_3),其中盾叶皂甙A_2的甙元为一新甾体皂甙元,命名为盾叶皂甙元(zingiberogenin)。  相似文献   
39.
目的:探讨三七、栀子有效组分及配伍给药对APP/PS1小鼠血清中乙酰胆碱和五羟色胺含量的影响及其与行为学的相关性分析。方法:APP/PS1小鼠随机分成转基因模型组(Tg)、三七总皂苷组(PNS)、栀子苷组(GP)、配伍组(PNS+GP),同窝非转基因小鼠为野生型组(WT),从4月龄开始,以自主进食的方式,分组给药3个月,7月龄时,进行八臂迷宫测试和血清中乙酰胆碱及五羟色胺含量的检测。结果:(1)乙酰胆碱含量测定结果,与野生型组相比,转基因模型组有显著性降低(P0.05);三七总皂苷组、栀子苷组可以显著升高转基因模型组的乙酰胆碱含量(P0.05)。(2)五羟色胺含量测定结果,与野生型组相比,转基因模型组有降低趋势,但无统计学意义(P0.05);三七总皂苷组、栀子苷组和配伍组对转基因组的五羟色胺含量有升高趋势,但都没有统计学意义(P0.05)。(3)相关性分析结果,八臂迷宫测试中小鼠进入食物臂的时间百分比与血清中乙酰胆碱的含量成正相关(r=0.35,P0.05),与血清中五羟色胺的含量没有相关性(rs=0.16,P=0.39)。结论:三七、栀子有效组分及配伍给药对APP/PS1小鼠血清中乙酰胆碱的含量有调节作用,APP/PS1小鼠血清中乙酰胆碱的含量与八臂迷宫行为学测试体现的空间学习记忆能力成正相关。  相似文献   
40.
 Hairy roots of Panax ginseng were obtained after root disks were infected with wild-type strain Agrobacterium rhizogenes 15834. Three lines of hairy roots with different pigmentation were selected. Embryogenic callus was induced on Murashige and Skoog medium containing 1.0 mg/l 2,4-D. The frequency of embryogenic callus formation was 37.4% in a line with red pigmentation. Somatic embryo development from embryogenic callus was efficiently achieved by lowering the concentration of 2,4-D (0.5 mg/l). After the germination of somatic embryos on medium with 10 mg/l GA3, the embryos were transferred to 1/2-MS medium without GA3. The transformed ginseng plantlets had an actively growing root system with abundant lateral roots. The phenotypical alteration of transformed ginseng plants might be valuable character for increasing root yield. Received: 27 March 1999 / Revision received: 18 May 1999 / Accepted 8 July 1999  相似文献   
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