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1.
A polysaccharide fraction was isolated form sodium-dodecyl-sulfate (SDS) treated cell walls of Bacillus anthracis (delta Sterne) by hydrofluoric acid (HF) hydrolysis and ethanolic precipitation. The polysaccharide fraction was subsequently purified by several washings with absolute ethanol. Purity of the isolated polysaccharide was tested using the anthrone assay and amino acid analyzer. The molecular mass of the polysaccharide fraction as determined by gel filtration chromatography was about 12000 Da. Preliminary analyses of the polysaccharide was done using thin layer chromatography and amino acid analyzer, and results obtained from these analyses were further confirmed by gas liquid chromatography and 13C-NMR spectroscopy. Results showed that the polysaccharide moiety contained galactose, N-acetylglucosamine, and N-acetylmannosamine in an approximate molar ratio of 3:2:1. This moiety was devoid of muramic acid, alanine, diaminopimelic acid, glutamic acid, and lipid, thus indicating that the isolated polysaccharide was of pure quality.  相似文献   

2.
The content of biologically active polypeptides in aqueous and ethanol extracts of seven sea anemone species collected near Sakhalin Island (Sea of Okhotsk) and in Posyet Bay (Sea of Japan) was analyzed. Water extracts of the sea anemone Cribrinopsis similis showed the highest hemolytic activity, while ethanol extracts proved to have toxic properties. The levels of toxic and hemolytic activity of extracts of sea anemones inhabiting northern temperate waters were 2 to 3 orders of magnitude lower, compared to tropic species. The reason for this is likely to be the differences in the habitat conditions and biological traits of these animals. The water extracts of all species possessed proteolytic, phospholipase A2, and low DNAase activities, except Actinostola sp., whose aqueous extract contained a high activity alkaline DNAase. The species studied contained a wide range of proteinase inhibitors, O-glycosyl hydrolases (glycosidases and polysaccharide hydrolases). Water extracts of C. similis and Stomphia coccinea possessed the highest laminarinase activity. High activity of N-galactopyranosidase was found in water extracts of S. coccinea and Oulactis orientalis.  相似文献   

3.
为改善毛头鬼伞子实体多糖的性状,以粗多糖得率、多糖含量、吸潮性及色素含量为指标,对乙醇沉淀制备多糖的参数进行了优化。结果表明:子实体经提取后浓缩至浓缩比为1∶2,即m(物料干质量/g)∶V(提取液/m L)=1∶2时以60%乙醇沉淀,再以60%乙醇洗涤1次,经冷冻干燥所得粗多糖产品多糖含量较高、色浅,且吸潮性降低,性状得到明显改善。  相似文献   

4.
The neural cell adhesion molecule L1 is critical for brain development and plays a role in learning and memory in the adult. Ethanol inhibits L1-mediated cell adhesion and neurite outgrowth in cerebellar granule neurons (CGNs), and these actions might underlie the cerebellar dysmorphology of fetal alcohol spectrum disorders. The peptide NAP potently blocks ethanol inhibition of L1 adhesion and prevents ethanol teratogenesis. We used quantitative RT-PCR and Western blotting of extracts of cerebellar slices, CGNs, and astrocytes from postnatal day 7 (PD7) rats to investigate whether ethanol and NAP act in part by regulating the expression of L1. Treatment of cerebellar slices with 20 mM ethanol, 10(-12) M NAP, or both for 4 hours, 24 hours, and 10 days did not significantly affect L1 mRNA and protein levels. Similar treatment for 4 or 24 hours did not regulate L1 expression in primary cultures of CGNs and astrocytes, the predominant cerebellar cell types. Because ethanol also damages the adult cerebellum, we studied the effects of chronic ethanol exposure in adult rats. One year of binge drinking did not alter L1 gene and protein expression in extracts from whole cerebellum. Thus, ethanol does not alter L1 expression in the developing or adult cerebellum; more likely, ethanol disrupts L1 function by modifying its conformation and signaling. Likewise, NAP antagonizes the actions of ethanol without altering L1 expression.  相似文献   

5.
6.
Licorice, the roots of Glycyrrhiza inflata, is used by practitioners of alternative medicine to treat individuals with gastric or duodenal ulcers, bronchitis, cough, arthritis, adrenal insufficiency, and allergies. We investigated the anti-inflammatory properties of 4 licorice extracts: extracts of roasted licorice obtained by ethanol (rLE) or water extraction (rLW) and extracts of raw licorice obtained by ethanol (LE) or water extraction (LW). rLE demonstrated strong anti-inflammatory activity through its ability to reduce nitric oxide and prostaglandin E(2) production in the LPS-stimulated mouse macrophage cell, RAW264.7. It also inhibited the production of pro-inflammatory cytokines and CD14 expression on the LPS-stimulated RAW264.7 cells. Further study indicated that LPS-induced degradation and phosphorylation of Ikappa-Balpha, along with DNA-binding of NF-kappaB, was significantly inhibited by rLE exposure in RAW264.7 cells. In the murine model, we found that in vivo exposure to rLE-induced an increase in the survival rate, reduced plasma levels of TNF-alpha and IL-6, and increased IL-10 production in LPS-treated mice. Collectively, these data suggest that the use of rLE may be a useful therapeutic approach to various inflammatory diseases.  相似文献   

7.
Live Tetrahymena thermophila transforms exogenous cholesterol into 7,22-bis, dehydrocholesterol (DHC) by desaturation at positions C7(8) and C22(23) of the cholesterol moiety. In this first report on expression, isolation, characterization, and reconstitution of Tetrahymena's cholesterol desaturases in cell-free extracts, we describe conditions for increasing the expression of both desaturases based on the addition of specific sterols to the culture medium. Reactions performed in vitro, with isolated microsomes, yield only the mono-unsaturated derivatives, 7-DHC and/or 22-DHC. However, selectivity towards one product can be improved with the addition of specific compounds: beta-mercaptoethanol inhibited C22(23) desaturase activity completely, while ethanol selectively increased this activity. Detergent-solubilized microsomes showed no desaturase activity, but partial restoration could be achieved with addition of dilauroyl-phosphatidylcholine liposomes (25%). Both cholesterol desaturases require molecular oxygen and cytochrome b(5). NADH or NADPH can serve as reduced cofactors, albeit with different efficiency, delivered by reductases present in the microsomal fraction. Azide and cyanide, but not azole compounds, inhibited these desaturases, suggesting a key role for cytochrome b(5) in these reactions.  相似文献   

8.
Petroleum ether (60 degrees-80 degrees C), chloroform, acetone, ethanol, aqueous and crude hot water extracts of the whole plant of C. dactylon and the two fractions of aqueous extract were tested for antihyperglycaemic activity in glucose overloaded hyperglycemic rats and in alloxan induced diabetic model at two-dose levels, 200 and 400 mg/kg (po) respectively. The aqueous extract of C. dactylon and the non polysaccharide fraction of aqueous extract were found to exhibit significant antihyperglycaemic activity and only the non polysaccharide fraction was found to produce hypoglycemia in fasted normal rats. Treatment of diabetic rats with aqueous extract and non polysaccharide fraction of the plant decreased the elevated biochemical parameters, glucose, urea, creatinine, serum cholesterol, serum triglyceride, high density lipoprotein, low density lipoprotein, haemoglobin and glycosylated haemoglobin significantly. Comparatively, the non polysaccharide fraction of aqueous extract was found to be more effective than the aqueous extract.  相似文献   

9.
CD147 plays a critical role in the invasive and metastatic activity of hepatocellular carcinoma (HCC) cells by stimulating the surrounding fibroblasts to secrete matrix metalloproteinases (MMPs). Tumor cells adhesion to extracellular matrix (ECM) proteins is the first step to the tumor metastasis. MMPs degrade the ECM to promote tumor metastasis. The aim of this research was to investigate the inhibitory effects of stealth small interfering RNA (siRNA) against CD147 on HCC cell line (SMMC-7721) metastatic properties including invasion, adhesion to ECM, gelatinase production, focal adhesion kinase (FAK) and vinculin expression. Flow cytometry (FCM) and western blot assays were employed to detect the transfection efficiency of the stealth siRNA against CD147. Invasion assays and gelatin zymography were also used to detect the effects of stealth siRNA against CD147 on SMMC-7721 cells’ invasion and gelatinase production. The effects of stealth siRNA against CD147 on FAK and vinculiln expression in SMMC-7721 cells were also detected by western blot. The results showed that stealth siRNA against CD147 inhibited SMMC-7721 invasion, adhesion to ECM proteins, MMP-2 production, and FAK and vinculin expression. These findings indicate that CD147 is required for tumor cell invasion and adhesion. Perturbation of CD147 expression may have potential therapeutic uses in the prevention of MMP-2-dependent tumor invasion.  相似文献   

10.
Different seed extracts from Coix lachryma-jobi (adlay seed) have been used for the treatment of various cancers in China, and clinical data support the use of these extracts for cancer therapy; however, their underlying molecular mechanisms have not been well defined. A polysaccharide fraction, designated as CP-1, was extracted from the C. lachryma-jobi L. var. using the ethanol subsiding method. CP-1 induced apoptosis in A549 cells in a dose-dependent manner, as determined by MTT assay. Apoptotic bodies were observed in the cells by scanning electronic microscopy. Apoptosis and DNA accumulation during S-phase of the cell cycle were determined by annexin V-FITC and PI staining, respectively, and measured by flow cytometry. CP-1 also extended the comet tail length on single cell gel electrophoresis, and disrupted the mitochondrial membrane potential. Further analysis by western blotting showed that the expression of caspase-3 and caspase-9 proteins was increased. Taken together, our results demonstrate that CP-1 is capable of inhibiting A549 cell proliferation and inducing apoptosis via a mechanism primarily involving the activation of the intrinsic mitochondrial pathway. The assay data suggest that in addition to its nutritional properties, CP-1 is a very promising candidate polysaccharide for the development of anti-cancer medicines.  相似文献   

11.
We report here the isolation and characterization of two active principles, ethyl 3',4',5'-trimethoxycinnamate (1) and piperine (2), from the combined hexane and chloroform extracts of Piper longum. Using primary human umbilical vein endothelial cells, we evaluated the activities of compound 1 on TNF-alpha-induced expression of cell adhesion molecules, viz., ICAM-1, VCAM-1, and E-selectin, which play key roles in controlling various inflammatory diseases. Both compounds 1 and 2 inhibited the TNF-alpha-induced expression of ICAM-1 in a dose- and time-dependent manner; however, the activity of ethyl 3',4',5'-trimethoxycinnamate (1) was approximately 1.3 times higher than that of piperine (2). As ethyl 3',4',5'-trimethoxycinnamate (1) has been isolated for the first time from a natural source, Piper longum, and it exhibited higher activity, we carried out further studies on it. To correlate its cell adhesion molecule inhibitory activity with its functional consequences, we showed that it significantly blocked the adhesion of neutrophils to endothelium in a time- and concentration-dependent manner. Importantly, the inhibitory effect of cinnamate 1 was found to be reversible. To elucidate its structure-function-activity relationship, we synthesized nine different analogues of ethyl 3',4',5'-trimethoxycinnamate, i.e., compounds 3-11, and compared the ICAM-1 inhibitory activity of compound 1 with those of its synthetic analogues as well as the corresponding acids 12-15. The structure-activity studies indicate that the chain length of the alcohol moiety, substituents in the aromatic ring, and alpha, beta-double bond of the cinnamic acid ester have significant effects on the inhibition of TNF-alpha-induced expression of ICAM-1 on endothelial cells. These findings have implications in developing compounds with a better therapeutic index against various inflammatory diseases.  相似文献   

12.
Zhao  Jianqiang  Ma  Lijie  Ni  Zengfeng  Liu  Hui 《Biotechnology letters》2021,43(7):1311-1322
Background

Bone marrow mesenchymal stem cells (BMMSCs) were proved to play a vital role in multiple myeloma (MM). Polygonatum sibiricum polysaccharide (PSP) was found to have anti-tumor pharmacological effects, yet its interaction with BMMSCs remained poorly understood. Therefore, we explore the effect of PSP on osteogenic differentiation of BMMSCs.

Methods

BMMSCs were isolated by density gradient centrifugation. CD90 and CD34 were detected by flow cytometry (FCM). Osteogenic marks were detected by quantitative real-time PCR (qRT-PCR) and Western blotting (WB). The vitality of cells treated with different concentrations of PSP was observed by Cell Counting Kit-8 (CCK-8). ALP staining kit was used to detect the activity of alkaline phosphatase (ALP). Alizarin red staining detected the formation of mineralized nodules. Osteoblast-associated genes were evaluated by qRT-PCR and WB. The phosphoinositide 3-kinase (PI3K), protein kinase B (AKT), and mammalian target of rapamycin (mTOR) signaling pathways were tested by WB.

Results

The BMMSCs showed good growth under an inverted microscope. FCM showed that CD34 and CD45 was low-expressed, whereas CD44, CD90 and CD105 was highly expressed. Compared with the Control group, the expressions of Runx2 and ALP in cells were significantly increased. CCK-8 showed that different concentrations of PSP had no significant effect on the viability of BMMSCs. BMMSCs treated with 25 mg/l PSP were stained the most deeply by ALP. Mineralized nodules in PSP groups dramatically increased, and hit a peak under the action of 25 mg/l PSP. PSP up-regulated p-PI3K, p-AKT, and p-mTOR, but had no significant effect on PI3K, AKT, and mTOR.

Conclusion

PSP induced osteogenic differentiation of BMMSCs from MM patients.

  相似文献   

13.
Ozone (O3) exposure of humans and animals induces an inflammatory response in the lung, which is associated with macrophage stimulation, release of chemotactic agents, and recruitment of polymorphonuclear leukocytes (PMNs). This study was designed to investigate the functional aspects of the macrophages that impact inflammatory processes in the lung. Macrophages recovered by bronchoalveolar lavage (BAL) from rats exposed to purified air or 0.8 ppm O3 were studied for their chemotactic activity, adhesive interactions with alveolar epithelial cells in culture, surface morphology, and surface expression of cell adhesion molecules. The macrophages isolated from O3-exposed rats exhibited a greater motility in response to a chemotactic stimulus than the macrophages isolated from rats exposed to purified air. The macrophages from O3-exposed animals also displayed greater adhesion when placed in culture with epithelial cells isolated from adult rat lung (ARL-14) than the macrophages from control rats. Both chemotactic motility and cell adhesion stimulated by O3 exposure were attenuated when the macrophages were incubated in the presence of monoclonal antibodies to leukocyte adhesion molecules, CD11b, or epithelial cell adhesion molecules, ICAM-1. Flow cytometry revealed a modest increase in the surface expression of CD11b but no change in ICAM-1 expression in macrophages from O3-exposed rats when compared to those from the air-exposed controls. The results demonstrate an alteration of macrophage functions following O3 exposure and suggest the dependence of these functions on the biologic characteristics, rather than the absolute expression, of the cell adhesion molecules. © 1996 Wiley-Liss, Inc.  相似文献   

14.
Pancreatic islet endothelial cells (ECs) form the barrier across which autoreactive T cells transmigrate during the development of islet inflammation in type 1 diabetes. Little is known about the immune phenotype of islet ECs that might shape their molecular interaction with autoreactive T cells before and during the development of islet inflammation. In this study we examined the expression and functional significance of costimulatory molecules by human islet ECs. Freshly isolated human islet ECs constitutively expressed CD86 (B7-2) and ICOS ligand but not CD80 (B7-1) or CD40 costimulatory molecules. The functional activity of islet EC-expressed CD86 was examined by coculture of resting islet ECs with CD4 T cells stimulated by CD3 ligation alone. Marked T cell proliferation in the coculture was completely abrogated by mAb blockade of CD86, confirming that costimulatory properties are conferred on ECs by CD86 expression. In view of its location on the vasculature, we hypothesized a role for CD86 in T cell adhesion/transmigration. In keeping with this, adhesion/transmigration of activated (CD3 ligated) memory (CD45R0(+)) CD4 T cells across islet ECs was completely inhibited in the presence of CD86 blocking mAb. Identical results were obtained for T cell adhesion using either CTLA-4 blocking mAb or CTLA-4Ig (abatacept), indicating CTLA-4 as the T cell ligand for these CD86-mediated effects. These data suggest a novel role for CD86 expression on the microvasculature, whereby ligation of CTLA-4 on CD4 T cells by CD86 on islet ECs is key to the adhesion of recently activated T cells.  相似文献   

15.
Systemic lupus erythematosus (SLE) is an autoimmune/inflammatory disease characterized by autoantibody production and abnormal T cells that infiltrate tissues through not well-known mechanisms. We report that SLE T lymphocytes display increased levels of CD44, ezrin, radixin, and moesin (ERM) phosphorylation, stronger actin polymerization, higher polar cap formation, and enhanced adhesion and chemotactic migration compared with T cells from patients with rheumatoid arthritis and normal individuals. Silencing of CD44 by CD44 small interfering RNA in SLE T cells inhibited significantly their ability to adhere and migrate as did treatment with Rho kinase and actin polymerization inhibitors. Forced expression of T567D-ezrin, a phosphorylation-mimic form, enhanced remarkably the adhesion and migration rate of normal T cells. Anti-CD3/TCR autoantibodies present in SLE sera caused increased ERM phosphorylation, adhesion, and migration in normal T cells. pERM and CD44 are highly expressed in T cells infiltrating in the kidneys of patients with lupus nephritis. These data prove that increased ERM phosphorylation represents a key molecular abnormality that guides T cell adhesion and migration in SLE patients.  相似文献   

16.
1. Several protein-polysaccharides were isolated from the soluble extracts of bovine heart valves by sedimentation equilibrium in a caesium chloride density gradient (Meyer, Preston & Lowther, 1969). 2. Compositional and structural studies indicated that the polysaccharide moiety was chondroitin sulphate. Differences in the protein content of the products were observed. There was no evidence suggesting the presence of keratan sulphate. 3. Sedimentation studies indicated that the molecular weights of the samples were between 4.2x10(4) and 6.5x10(4). The results are discussed in terms of a basic model for the protein-polysaccharides of two polysaccharide chains linked by a protein of variable size.  相似文献   

17.
Atherosclerosis, which manifests as acute coronary syndrome, stroke, and peripheral arterial diseases, is a chronic inflammatory disease of the arterial wall. Prunella vulgaris, a perennial herb with a worldwide distribution, has been used as a traditional medicine in inflammatory disease. Here, we investigated the effects of P. vulgaris ethanol extract on TNF-α-induced inflammatory responses in human aortic smooth muscle cells (HASMCs). We found that P. vulgaris ethanol extract inhibited adhesion of monocyte/macrophage-like THP-1 cells to activated HASMCs. It also decreased expression of intercellular adhesion molecule-1, vascular cell adhesion molecule-1, E-selectin and ROS, No production in TNF-α-induced HASMCs and reduced NF-kB activation. Furthermore, P. vulgaris extract suppressed TNF-α-induced phosphorylation of p38 mitogen-activated protein kinase (MAPK) and extracellular signal-regulated kinase (ERK). These results demonstrate that P. vulgaris possesses antiinflammatory properties and can regulate TNF-α-induced expression of adhesion molecules by inhibiting the p38 MAPK/ ERK signaling pathway. [BMB Reports 2013; 46(7): 352-357]  相似文献   

18.
Immune system impairment and increased susceptibility to infection among alcohol abusers is a significant but not well-understood problem. We hypothesized that acute ethanol administration would inhibit leukocyte recruitment and endothelial cell activation during inflammation and infection. Using LPS and carrageenan air pouch models in mice, we found that physiological concentrations of ethanol (1-5 g/kg) significantly blocked leukocyte recruitment (50-90%). Because endothelial cell activation and immune cell-endothelial cell interactions are critical regulators of leukocyte recruitment, we analyzed the effect of acute ethanol exposure on endothelial cell activation in vivo using the localized Shwartzman reaction model. In this model, ethanol markedly suppressed leukocyte accumulation and endothelial cell adhesion molecule expression in a dose-dependent manner. Finally, we examined the direct effects of ethanol on endothelial cell activation and leukocyte-endothelial cell interactions in vitro. Ethanol, at concentrations within the range found in human blood after acute exposure and below the levels that induce cytotoxicity (0.1-0.5%), did not induce endothelial cell activation, but significantly inhibited TNF-mediated endothelial cell activation, as measured by adhesion molecule (E-selectin, ICAM-1, VCAM-1) expression and chemokine (IL-8, MCP-1, RANTES) production and leukocyte adhesion in vitro. Studies exploring the potential mechanism by which ethanol suppresses endothelial cell activation revealed that ethanol blocked NF-kappaB nuclear entry in an IkappaBalpha-dependent manner. These findings support the hypothesis that acute ethanol overexposure may increase the risk of infection and inhibit the host inflammatory response, in part, by blocking endothelial cell activation and subsequent immune cell-endothelial cell interactions required for efficient immune cell recruitment.  相似文献   

19.
Using microfluidic assays at a 100 s?1 wall shear rate, we examined the effects of ethanol on cholesterol-loaded neutrophils with respect to: (1) collision efficiency and membrane tethering to P-selectin-coated microbeads, (2) rolling on P-selectin-coated surfaces, and (3) primary and secondary interactions with neutrophils pre-adhered to intercellular adhesion molecule-1 (ICAM-1). Using methyl-β-cyclodextrin:cholesterol complexes, membrane cholesterol was increased over control by 4.6-fold (no ethanol), 3.6-fold (0.3% ethanol pre-loading), and 1.6-fold (0.3% ethanol post-loading). These treatments did not alter CD11b expression; however, PSGL-1 and L-selectin were lowered by cholesterol enrichment (±ethanol). Cholesterol enrichment enhanced microbead collision efficiency, which was abrogated by ethanol. Ethanol had no effect on elevation of tethering fraction by cholesterol enrichment. Incubation of cholesterol-loaded neutrophils with ethanol resulted in significantly longer membrane tethers, due to tether lifetime enhancement. On P-selectin-coated surfaces, cholesterol-enriched neutrophils exposed to ethanol rolled faster and with more variability than cholesterol-enriched neutrophils. Ethanol reduced homotypic collision efficiency of cholesterol-loaded neutrophils without effect on tethering fraction or secondary collision efficiency. Tether length during cholesterol-loaded neutrophil homotypic collisions was enhanced by ethanol, in part due to increased L-selectin/PSGL-1 bond tether lifetime. Overall, ethanol attenuated cholesterol-induced adhesion increases while increasing membrane fluidity as indicated by tether length.  相似文献   

20.
In multiple sclerosis, activated CD4(+) T cells initiate an immune response in the brain and spinal cord, resulting in demyelination, degeneration and progressive paralysis. Repulsive guidance molecule-a (RGMa) is an axon guidance molecule that has a role in the visual system and in neural tube closure. Our study shows that RGMa is expressed in bone marrow-derived dendritic cells (BMDCs) and that CD4(+) T cells express neogenin, a receptor for RGMa. Binding of RGMa to CD4(+) T cells led to activation of the small GTPase Rap1 and increased adhesion of T cells to intracellular adhesion molecule-1 (ICAM-1). Neutralizing antibodies to RGMa attenuated clinical symptoms of mouse myelin oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalomyelitis (EAE) and reduced invasion of inflammatory cells into the CNS. Silencing of RGMa in MOG-pulsed BMDCs reduced their capacity to induce EAE following adoptive transfer to naive C57BL/6 mice. CD4(+) T cells isolated from mice treated with an RGMa-specific antibody showed diminished proliferative responses and reduced interferon-γ (IFN-γ), interleukin-2 (IL-2), IL-4 and IL-17 secretion. Incubation of PBMCs from patients with multiple sclerosis with an RGMa-specific antibody reduced proliferative responses and pro-inflammatory cytokine expression. These results demonstrate that an RGMa-specific antibody suppresses T cell responses, and suggest that RGMa could be a promising molecular target for the treatment of multiple sclerosis.  相似文献   

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