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1.
Cheng JJ  Huang NK  Chang TT  Wang DL  Lu MK 《Life sciences》2005,76(26):3029-3042
The main purposes of this study were to investigate the regulation of polysaccharides isolated from A. cinnamomea on vascular endothelial growth factor (VEGF)-induced cyclin D1 expression and down stream signaling pathway that may correlate with their anti-angiogenc effects in endothelial cells (ECs). Crude and fractionated polysaccharides (Fra-1 to Fra-4) of A. cinnamomea showed slightly toxicity to ECs as compared with their inhibition concentration on angiogenic-related gene expression. The crude extract and fractionated fractions, except for Fra-2, of A. cinnamomea polysaccharides significantly decreased VEGFR2 phosphorylation on tyrosine 1054/1059, cyclin D1 promotor activity, and protein expression induced by VEGF. Crude extract of A. cinnamomea polysaccharides inhibited the binding of VEGF to KDR/flk-1 in a dose-dependent manner. These results indicated that inhibition of VEGF interaction with VEGF receptor 2 is the mechanism serves A. cinnamomea as a protective mechanism composing the anti-angiogenesis function. Furthermore, A. cinnamomea polysaccharides also blocked VEGF-induced migration and capillary-like tube formation of ECs on Matrigel. Taken together, these results indicate that A. cinnamomea polysaccharides inhibit cyclin D1 expression through inhibition of VEGF receptor signaling, leading to the suppression of angiogenesis.  相似文献   

2.
The species of Antrodia are one of the difficult-to-classify and obscure groups of poroid Aphyllophorales based on morphological appearance. However, it is becoming increasingly important to reliably identify the entire suite of Antrodia camphorata strains and Antrodia species due to the potential pharmaceutical value of their biologically active ingredients. In this study, the internal transcribed spacer (ITS) region of the ribosomal RNA gene (rDNA) was sequenced and phylogenetically analyzed in a number of Antrodia fungal species and strains. ITS amplicons from the Antrodia species tested ranged in size from 543 to 610 bp; the size of the ITS of A. camphorata strains ranged from 592 to 596 bp. The overall sizes of ITS2 and 5.8S ribosomal RNA gene of all A. camphorata strains tested in this study were shown to be 217 and 158 bp, respectively. A phylogenetic analysis of ITS data generated, which included sequences of 11 A. camphorata strains and nine other Antrodia species, showed three clearly distinct groups. Group 1 includes A. camphorata, Antrodia salmonea, and Antrodia carbinca strains. Within Group 2, Antrodia sinuosa and Antrodia xantha were clustered together. Group 3 contained Antrodia albida, A. heteromorpha, A. serialis, and A. malicola. The observed sequence diversity among ITS alleles provided an effective tool for differentiating strains of A. camphorata, A. salmonea, A. xantha, A. sinuosa, or A. serialis. Polymorphisms arising within the ITS1-5.8S-ITS2 region can provide practical markers for establishing a foundation for the further expansion of an ITS sequence database of medically important fungi.  相似文献   

3.
赵能  原晓龙  陈剑  陈中华  王娟  杨宇明  王毅 《广西植物》2017,37(8):1068-1073
牛樟芝作为一种珍稀食用和药用菌,具有极大的开发潜力。该研究以麦芽浸粉肉汤液体培养基(BD,美国BD公司)对牛樟芝菌丝体进行摇床培养60 d后,收获发酵液并用乙酸乙酯对其进行萃取,浓缩至干获得提取物;同时,采用抑菌圈法评价培养物对13种致病细菌抗菌活性(蜡样芽孢杆菌、缓慢芽孢杆菌、无乳链球菌、短小芽孢杆菌、福氏志贺氏菌、枯草芽孢杆菌、金黄色葡萄球菌、藤黄微球菌、副溶血性弧菌、溶血性葡萄球菌、铜尿假单胞菌、乙型副伤寒沙门氏菌、大肠埃希菌),并检测相应致病细菌的最低抑制浓度(MIC)。结果表明:牛樟芝麦芽浸粉肉汤发酵液提取物对供试的13种致病菌均有抑菌活性;在供试的13种致病菌中,提取物对缓慢芽孢杆菌、短小芽孢杆菌、枯草芽孢杆菌、副溶血性弧菌、藤黄微球菌5种致病菌的最低抑制浓度值均小于80μg·m L~(-1),其中对藤黄微球菌的最低抑制浓度最低为66.5μg·m~(-1);随着培养时间的增加,提取物的抗菌活性也增加。这说明牛樟芝菌丝体在液体培养条件下,能够产生广谱高效抑菌活性的次生代谢产物。该研究结果为牛樟芝进一步的有效利用开发奠定了理论基础。  相似文献   

4.
在四川青城山风景区发现木材腐朽菌60种,给出了每个木材腐朽菌的寄主和生长基质。拟黄薄孔菌Antrodia subxantha为一新种,其特点为子实体平伏,孔口表面黄色,担孢子圆柱形至窄椭圆形(3-4×1.6-2.1μm),菌髓主要由生殖菌丝组成;该种与黄薄孔菌Antrodia xantha具有相似的孔口表面,但后者的担孢子为腊肠形(4-5×1.2-1.5μm),且其菌髓主要有骨架菌丝组成。  相似文献   

5.
Chen YY  Chou PY  Chien YC  Wu CH  Wu TS  Sheu MJ 《Phytomedicine》2012,19(8-9):768-778
Cancer metastasis is a primary cause of cancer death. Antrodia cinnamomea (A. cinnamomea), a medicinal mushroom in Taiwan, has been shown antioxidant and anticancer activities. In this study, we first observed that ethanol extract of fruiting bodies of A. cinnamomea (EEAC) exerted a concentration-dependent inhibitory effect on migration and motility of CL1-0 cells in the absence of cytotoxicity. The results of a gelatin zymography assay showed that A. cinnamomea suppressed the activity of matrix metalloproteinase (MMP)-2 and MMP-9 in a concentration-dependent manner. Western blot results demonstrated that treatment with A. cinnamomea decreased the expression of MMP-9 and MMP-2; while the expression of the endogenous inhibitors of these proteins, i.e., tissue inhibitors of MMP (TIMP-1 and TIMP-2) increased. Two major compounds from EEAC codycepin and zhankuic acid A alone and together inhibited MMP-9 and MMP-2 expressions. Further investigation revealed that A. cinnamomea suppressed the phosphorylation of p38, and JNK1/2. A. cinnamomea also suppressed the expressions of PI3K and phosphorylation of AKT. This is the first report confirming the anti-migration activity of this potentially beneficial mushroom against human lung adenocarcinoma CL1-0.  相似文献   

6.
It is of interest to document the insights gleaned from the cDNA and EST analysis of Antrodia cinnamomea (a fungal species). Hence a library of sequences was constructed and analysed using standard procedures to gain new insights. Therefore, 65 ESTs, with size ranging from 300-2000 bp, were constructed. This included 46 ESTs with definite annotation, 18 ESTs were hypothetical and 1 new protein derived from BLAST analysis. We assigned 227 Gene Ontology terms linked to cell composition, transport, catalytic activity, and regulation functions in these sequences. Moreover, 56 matching genes were found in 8 Kyoto Encyclopedia of Genes and Genomes pathways. Data also showed 271 SSRs from Antrodia cinnamomea ESTs with an occurrence frequency of 96.82%. The STRING data analysis showed 29 genes encoded enzymes highly involved in protein-to-protein interactions linked to expression of regulation function. Thus, we documented some insights from the cDNA and EST analysis of Antrodia cinnamomea for further data mining.  相似文献   

7.
大兴安岭林区火烧迹地木腐菌主要类群的初步研究   总被引:4,自引:0,他引:4  
对大兴安岭林区火烧迹地的17种主要木腐菌进行了报道,并就它们的生态习性和生态功能进行探讨.通过对火烧林分和非过火林分主要木腐菌类群变化的研究,确定在火烧迹地森林生态系统演替过程中的先锋菌物主要有8种,常见菌4种,以及在寒温带针叶林生态系统中的珍稀和濒危的木腐菌3种,并探讨了珍稀或濒危菌物的保护对策.  相似文献   

8.
Lu MK  Cheng JJ  Lai WL  Lin YR  Huang NK 《Life sciences》2006,79(3):252-258
Antrodia cinnamomea (formerly named Antrodia camphorata) is a rare medicinal fungus. We previously reported that it exhibits antioxidative, vasorelaxative, anti-inflammatory, and anti-angiogenic effects. When serum deprivation-induced apoptosis in neuronal-like PC12 cells was used as a stress model, the extract of A. cinnamomea displayed effectiveness in preventing serum-deprived apoptosis. Since our previous data show that the extract of A. cinnamomea contains adenosine (ADO), we attempt to investigate if the active component is ADO and to identify its targeting site in this study. After pre-incubation with ADO deaminase, neither ADO nor the extract of A. cinnamomea exerted any protection, demonstrating that the active component of A. cinnamomea is ADO. Furthermore, an ADO A(2A) receptor (A(2A)-R) antagonist was used and was able to block the protective effects of ADO and the extract of A. cinnamomea, demonstrating that the ADO targeting site in this model is A(2A)-R. Taken together, the protective effect of A. cinnamomea is owed to its active component, ADO, which acts through activation of A(2A)-R to prevent serum deprivation-induced PC12 cell apoptosis.  相似文献   

9.
目的:探讨新生血管特异性结合肽GX1二聚体对视网膜新生血管生成的影响。方法:化学合成GX1二聚体、GX1单体、对照肽二聚体,通过CCK-8实验、管状结构形成实验、迁移实验研究GX1二聚体对大鼠视网膜内皮细胞(RMEC)增殖、微管形成、迁移能力的影响,流式细胞学技术分析其对细胞周期分布和凋亡的影响。结果:CCK-8结果显示,与对照肽二聚体及阴性对照组相比,100-200μM GX1二聚体及单体均可抑制RMEC增殖(P<0.05),且随着GX1二聚体及单体浓度升高,抑制作用逐渐增强,呈剂量依赖性;各浓度GX1二聚体均较单体抑制作用增强,并有统计学差异(P<0.05)。管状结构形成实验、细胞损伤迁移实验结果显示与对照肽二聚体及PBS组相比,GX1二聚体及GX1单体均可明显抑制视网膜内皮细胞管状结构的形成及迁移,且二聚体抑制作用强于单体;对照肽二聚体仅有轻微的抑制视网膜内皮细胞管状结构形成的作用,对细胞迁移无明显抑制作用。流式细胞术分析显示与对照肽及阴性对照组相比,GX1二聚体及GX1单体均可诱导细胞凋亡(P<0.05),且GX1二聚体的诱导作用强于GX1单体(P<0.05),而对细胞周期分布则无明显影响。结论:GX1二聚体和GX1单体均可抑制视网膜新生血管内皮细胞增殖、微管形成、迁移能力及诱导凋亡,且GX1二聚体较GX1单体作用增强。GX1二聚体有望代替单体成为糖尿病视网膜病变新生血管靶向治疗小肽类药物。  相似文献   

10.
11.

Background

Glucocorticoid-mediated inhibition of angiogenesis is important in physiology, pathophysiology and therapy. However, the mechanisms through which glucocorticoids inhibit growth of new blood vessels have not been established. This study addresses the hypothesis that physiological levels of glucocorticoids inhibit angiogenesis by directly preventing tube formation by endothelial cells.

Methodology/Principal Findings

Cultured human umbilical vein (HUVEC) and aortic (HAoEC) endothelial cells were used to determine the influence of glucocorticoids on tube-like structure (TLS) formation, and on cellular proliferation (5-bromo-2′-deoxyuridine (BrdU) incorporation), viability (ATP production) and migration (Boyden chambers). Dexamethasone or cortisol (at physiological concentrations) inhibited both basal and prostaglandin F (PGF)-induced and vascular endothelial growth factor (VEGF) stimulated TLS formation in endothelial cells (ECs) cultured on Matrigel, effects which were blocked with the glucocorticoid receptor antagonist RU38486. Glucocorticoids had no effect on EC viability, migration or proliferation. Time-lapse imaging showed that cortisol blocked VEGF-stimulated cytoskeletal reorganisation and initialisation of tube formation. Real time PCR suggested that increased expression of thrombospodin-1 contributed to glucocorticoid-mediated inhibition of TLS formation.

Conclusions/Significance

We conclude that glucocorticoids interact directly with glucocorticoid receptors on vascular ECs to inhibit TLS formation. This action, which was conserved in ECs from two distinct vascular territories, was due to alterations in cell morphology rather than inhibition of EC viability, migration or proliferation and may be mediated in part by induction of thrombospodin-1. These findings provide important insights into the anti-angiogenic action of endogenous glucocorticoids in health and disease.  相似文献   

12.
Rigidoporus ulmarius is used as a medicinal fungus in Asia. Three isolates (denoted #61, #62, and #63) of R. ulmarius were collected, and their biological activities were evaluated. Extracted polysaccharides from isolate #63 showed greater inhibition activity compared to isolates #61 and #62 in an in vitro endothelial cell tube formation assay, a standard evaluation of angiogenesis. The polysaccharides and ethanolic extract of isolate #63 dose-dependently suppressed the production of the interferon (IFN)-γ-induced inflammation marker, IP-10. Chemical analyses of the polysaccharides revealed that isolate #63 contained the highest value of fucose at a concentration of 59.1 ± 1.2 μmol/g polysaccharide. These results suggest that fucose-containing polysaccharides may play a role in the inhibitory effect. Isolate #63 showed the highest values of ADP among the three isolates in the ethanolic extract. These results suggest that different isolates from R. ulmarius exhibit different abilities to regulate antiangiogenic and anti-inflammatory processes.  相似文献   

13.
白花蛇舌草多糖的分离提取及含量测定   总被引:12,自引:0,他引:12  
凌育赵 《生物技术》2005,15(4):48-50
采用热水浸提法提取白花蛇舌草水溶性多糖,薄层层析法鉴定其多糖的单糖组成。通过正交试验优选浸提显色条件,以苯酚-硫酸法制得有色糖醛衍生物,用分光光度法在490nm波长处测定吸光度,其曲线方程为Y=0.01361x-0.08161,相关系数r=0.9997。结果表明,白花蛇舌草多糖由鼠李糖、葡萄糖、半乳糖及甘露糖等组成,含量为15.10%,回收率达95.68%。  相似文献   

14.
Transforming growth factor-β (TGF-β) is a multifunctional cytokine that is known to modulate various aspects of endothelial cell (EC) biology. Retinal pigment epithelium (RPE) is important for regulating angiogenesis of choriocapillaris and one of the main cell sources of TGF-β secretion, particularly TGF-β2. However, it is largely unclear whether and how TGF-β2 affects angiogenic responses of ECs. In the current study, we demonstrated that TGF-β2 reduces vascular endothelial growth factor receptor-2 (VEGFR-2) expression in ECs and thereby inhibits vascular endothelial growth factor (VEGF) signaling and VEGF-induced angiogenic responses such as EC migration and tube formation. We also demonstrated that the reduction of VEGFR-2 expression by TGF-β2 is due to the suppression of JNK signaling. In coculture of RPE cells and ECs, RPE cells decreased VEGFR-2 levels in ECs and EC migration. In addition, we showed that TGF-β2 derived from RPE cells is involved in the reduction of VEGFR-2 expression and inhibition of EC migration. These results suggest that TGF-β2 plays an important role in inhibiting the angiogenic responses of ECs during the interaction between RPE cells and ECs and that angiogenic responses of ECs may be amplified by a decrease in TGF-β2 expression in RPE cells under pathologic conditions.  相似文献   

15.
16.
《Experimental mycology》1990,14(1):84-88
Rust fungi are obligate plant parasites whose successful parasitism appears to depend on the formation of haustoria within living plant cells. To test the hypothesis that the lack of haustorium formation in the absence of a living cell reflects a need for a simple “signal” released during attempted invasion, various carbohydrates were applied toin vitro-formed infection structures ofUromyces vignae just prior to haustorial mother cell (HMC) formation. Up to 6% of HMCs formed haustoria after treatment with arabinose, mannose, xylose, sucrose, or xylan. Other monosaccharides, oligosaccharides, and polysaccharides were less or not effective. Sugar mixtures induced haustorium frequencies of up to 10%. Timing of the application of inducing chemicals was critical. The data indicate that haustorium formation does not require the presence of a living plant cell and may be triggered by plant products at the time of penetration peg development.  相似文献   

17.
The antibiotic, tsushimycin, inhibits the formation of dolichyl phosphate mannose, dolichyl phosphate glucose and dolichyl pyrophosphate N-acetylglucosamine in the particulate enzyme preparation from pig aorta. Although this antibiotic also inhibits the incorporation of mannose and glucose into lipid-linked oligosaccharides, these reactions are less sensitive to antibiotic than those involved in the synthesis of lipid-linked monosaccharides. In the presence of tsushimycin, most of the mannose incorporated into lipid-linked oligosaccharides is into one oligosaccharide that has the properties of the heptasaccharide Man5GlcNAc2, whereas in the absence of antibiotic most of the mannose is in larger-sized oligosaccharides. On the other hand, the glucose-labelled lipid-linked oligosaccharides appear to be similar in size in the presence or absence of antibiotic. Tsushimycin also inhibits the formation of lipid-linked monosaccharides by the solubilized enzyme preparation of aorta. Various concentrations of dolichyl phosphate or the detergent, Nonidet P40, had no effect on antibiotic inhibition. Some evidence indicates that tsushimycin binds to the particulate enzyme.  相似文献   

18.
The highly sialylated vascular endothelial surface undergoes changes in sialylation upon adopting the migratory/angiogenic phenotype. We recently established endothelial cell (EC) expression of NEU1 sialidase (Cross, A. S., Hyun, S. W., Miranda-Ribera, A., Feng, C., Liu, A., Nguyen, C., Zhang, L., Luzina, I. G., Atamas, S. P., Twaddell, W. S., Guang, W., Lillehoj, E. P., Puché, A. C., Huang, W., Wang, L. X., Passaniti, A., and Goldblum, S. E. (2012) NEU1 and NEU3 sialidase activity expressed in human lung microvascular endothelia. NEU1 restrains endothelial cell migration whereas NEU3 does not. J. Biol. Chem. 287, 15966–15980). We asked whether NEU1 might regulate EC capillary-like tube formation on a Matrigel substrate. In human pulmonary microvascular ECs (HPMECs), prior silencing of NEU1 did not alter tube formation. Infection of HPMECs with increasing multiplicities of infection of an adenovirus encoding for catalytically active WT NEU1 dose-dependently impaired tube formation, whereas overexpression of either a catalytically dead NEU1 mutant, NEU1-G68V, or another human sialidase, NEU3, did not. NEU1 overexpression also diminished EC adhesion to the Matrigel substrate and restrained EC migration in a wounding assay. In HPMECs, the adhesion molecule, CD31, also known as platelet endothelial cell adhesion molecule-1, was sialylated via α2,6-linkages, as shown by Sambucus nigra agglutinin lectin blotting. NEU1 overexpression increased CD31 binding to Arachis hypogaea or peanut agglutinin lectin, indicating CD31 desialylation. In the postconfluent state, when CD31 ectodomains are homophilically engaged, NEU1 was recruited to and desialylated CD31. In postconfluent ECs, CD31 was desialylated compared with subconfluent cells, and prior NEU1 silencing completely protected against CD31 desialylation. Prior CD31 silencing and the use of CD31-null ECs each abrogated the NEU1 inhibitory effect on EC tube formation. Sialyltransferase 6 GAL-I overexpression increased α2,6-linked CD31 sialylation and dose-dependently counteracted NEU1-mediated inhibition of EC tube formation. These combined data indicate that catalytically active NEU1 inhibits in vitro angiogenesis through desialylation of its substrate, CD31.  相似文献   

19.
Interactions between astrocytes and endothelial cells (ECs) are crucial for retinal vascular formation. Astrocytes induce migration and proliferation of ECs via their production of vascular endothelial growth factor (VEGF) and, conversely, ECs induce maturation of astrocytes possibly by the secretion of leukemia inhibitory factor (LIF). Together with the maturation of astrocytes, this finalizes angiogenesis. Thus far, the mechanisms triggering LIF production in ECs are unclear. Here we show that apelin, a ligand for the endothelial receptor APJ, induces maturation of astrocytes mediated by the production of LIF from ECs. APJ (Aplnr)- and Apln-deficient mice show delayed angiogenesis; however, aberrant overgrowth of endothelial networks with immature astrocyte overgrowth was induced. When ECs were stimulated with apelin, LIF expression was upregulated and intraocular injection of LIF into APJ-deficient mice suppressed EC and astrocyte overgrowth. These data suggest an involvement of apelin/APJ in the maturation process of retinal angiogenesis.  相似文献   

20.
Embryonic blood vessel formation is initially mediated through the sequential differentiation, migration, and assembly of endothelial cells (ECs). While many molecular signals that promote vascular development have been identified, little is known about suppressors of this process. In higher vertebrates, including birds and mammals, the vascular network forms throughout the embryonic disk with the exception of a region along the midline. We have previously shown that the notochord is responsible for the generation and maintenance of the avascular midline and that BMP antagonists expressed by this embryonic tissue, including Noggin and Chordin, can mimic this inhibitory role. Here we report that the notochord suppresses the generation of ECs from the mesoderm both in vivo and in vitro. We also report that the notochord diminishes the ability of mature ECs to organize into a primitive plexus. Furthermore, Noggin mimics notochord-based inhibition by preventing mesodermal EC generation and mature EC network formation. These findings suggest that the mesoderm surrounding the midline is competent to give rise to ECs and to form blood vessels, but that notochord derived-BMP antagonists suppress EC differentiation and maturation processes leading to inhibition of midline vessel formation.  相似文献   

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