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31.
目的:观察糖痹康大鼠含药血清对高糖造成人脐静脉内皮细胞(HUVEC)损伤的保护作用。方法:以CCK-8法观察不同浓度葡萄糖对人脐静脉内皮细胞活力的影响;根据实验结果选择葡萄糖浓度为5.55mmol/L组为正常组,葡萄糖浓度为25mmol/L组做为模型组。然后制备正常组,弥可保组,糖痹康组的大鼠含药血清,将含药血清作用于高糖损伤的人脐静脉内皮细胞,分为正常组、高糖模型组、高糖弥可保组、高糖糖痹康低、中、高剂量组,并通过测定培养液中丙二醛(MDA)、乳酸脱氢酶(LDH)、一氧化氮(NO)含量与超氧化物歧化酶(SOD)活力,探讨糖痹康对血管内皮细胞损伤的保护作用。结果:与高糖模型组比较,糖痹康含药血清能减少细胞MDA、LDH释放量,提高SOD活力及NO含量。结论:糖痹康对高糖损伤的血管内皮细胞有一定的保护作用,间接的起到对周围神经的保护作用。  相似文献   
32.
Rheumatoid arthritis (RA) is associated with a reduced life expectancy considered to be partly caused by cardiovascular events. A growing concern is that accelerated atherosclerosis is driven by inflammatory mechanisms similar to those responsible for RA. Therefore, selective COX-2 inhibitors, which are widely used for the symptomatic treatment of pain and inflammation in RA, may have an impact on atherosclerotic processes. Their anti-inflammatory properties might provoke anti-atherogenic effects but on the other hand, selective inhibition of anti-thrombotic prostacyclin and COX-2 independent effects might promote the risk of increased prothrombotic activity. In the current study, the effects of the presently marketed selective COX-2 inhibitors celecoxib and rofecoxib on vascular cells have been investigated. Celecoxib inhibited the proliferation of human umbilical vein endothelial cells (HUVECs) in a concentration-dependent manner. At high concentrations, it induced apoptosis and the modulation of inhibitory cell cycle proteins. In contrast rofecoxib-even at high concentrations-had no effect on cell proliferation, apoptosis or cell cycle distribution indicating that celecoxib and rofecoxib do not affect the same signal transduction pathways in endothelial cells. Both drugs did not affect apoptosis induction or cell cycle proliferation in human vascular smooth muscle cells. The observed effects on endothelial cells appear to be COX-independent since both drugs selectively inhibited COX-2-activity and the applied concentrations lay beyond the IC(50) for inhibition of prostacyclin production. Regarding endothelial apoptosis as a relevant event in the initiation and progression of atherosclerosis the present data put forward the hypothesis that the presently marketed COX-2 inhibitors have a different impact on atherosclerotic processes.  相似文献   
33.
目的探讨缸鱼软骨多糖(RCG)对人脐静脉内皮细胞形成新生血管的作用.方法原代培养人脐静脉内皮细胞,实验分为生理氯化钠溶液(NS)对照组、RCG 100,50,25,10,2 g·L-1组和阳性对照鲨鱼软骨多糖(SCG,50 g·L-1)组.采用MTT法检测RCG对HUVEC增殖的影响,流式细胞仪检测RCG对HUVEC细胞周期的影响;并观察RCG对HUVEC迁移及小管形成的作用.结果10~100 g·L-1RCG可明显抑制HUVEC的体外增殖,IC50为62.93 g·L-1.流式细胞仪检测表明,RCG阻止HUVEC在G2/M期.10~100g·L-1 RCG明显抑制HUVEC迁移和小管形成.结论RCG具有良好的体外抗血管生成活性.  相似文献   
34.
Dimerization of inducible NOS has been known to be a potential therapeutic target for iNOS-mediated pathologies. Cyclic dipeptides are among the simplest peptides commonly found as by-products of food processing or metabolites of microorganisms. In this study, we found that cyclo(dehydrohistidyl-l-tryptophyl) (CDHT), a cyclic dipeptide from an unidentified fungal strain Fb956, prevents iNOS dimerization in activated microglial BV-2 cells. CDHT inhibited NO production with an IC50 of 6.5 microM in LPS-treated BV-2 cells. Western blot analysis and iNOS activity measurement of fractions from size-exclusion chromatography of cell lysates indicated that CDHT inhibits dimerization of iNOS, while it has no effect on iNOS expression or enzyme activity. The CDHT inhibition of iNOS dimerization was confirmed by partially denaturing SDS-PAGE analysis. In contrast, CDHT did not affect cGMP production in endothelial HUVEC cells, which indicates no inhibition of endothelial NOS activity. These results reveal that CDHT, one of the simplest and cyclic dipeptides, selectively inhibits NO production by inhibiting iNOS dimerization, and could be a useful therapeutic agent for inflammation-mediated diseases.  相似文献   
35.
Dysfunction of endothelial cells and activation of monocytes in the vascular wall are important pathogenetic factors of atherosclerosis. Conjugated linoleic acids (CLAs) can modulate the function of immune system in humans: reduce the concentration of atherogenic lipoproteins, and the intensity of inflammatory processes in the plasma. In this paper, we focus on macrophage's surface integrins (β1 integrin CD49d/CD29-(VLA4); Mac-1 as well as endothelial human vein endothelial cell (HUVEC) surface adhesins: vascular cell adhesion molecule-1 (VCAM-1) and intracellular cell adhesion molecule-1 (ICAM-1)) expression in relation to CLA isomer used during cell culture. Both CLA isomers decreased expression of VLA-4 and Mac-1 on macrophages compared with control cells (cultured with bovine serum albumine (BSA) or oxidized form of low-density lipoproteins). cis-9, trans-11 CLA isomer reduced ICAM-1 and VCAM-1 expression on the endothelium surface. Strong tendency to reduce of adhesion of macrophages to HUVEC in the cells cultured with CLA isomers was observed. The potential role of cis-9, trans-11 CLA in the reduction of adhesion of macrophages to the HUVEC – one of the important steps in the inflammatory process, can be considerate. These mechanisms may contribute to the potent anti-atherosclerotic effects of CLA in vivo.  相似文献   
36.
目的:通过建立H2O2 导致人脐静脉内皮细胞损伤的模型来研究狭鳕鱼皮胶原蛋白肽作用。方法:用人脐静脉内皮细胞作为体外研究对象,采用不同的浓度(40M、200M、400M)胶原蛋白和维生素E预处理12h,然后在加入50uM H2O2继续培养12h造成损伤模型。模型成功后用CCK-8检测吸光度,根据试剂盒操作检测细胞内及培养上清液谷胱甘肽过氧化物酶(GXH-PX),一氧化氮(NO)、过氧化氢酶(CAT),丙二醛(MDA)等指标的含量和活性变化。结果:经胶原蛋白预保护后细胞增值率升高,GXH-PX、CAT等活性增强,NO含量升高,丙二醛含量降低。  相似文献   
37.
Polyacetylenes Function as Anti-Angiogenic Agents   总被引:1,自引:0,他引:1  
PURPOSE: To investigate the antiangiogenic effects of plant extracts and polyacetylenes isolated from Bidens pilosa Linn., which is a popular nutraceutical herbal tea and folk medicine in anti-inflammatory, antitumor, and other medications worldwide. METHODS: Anti-cell proliferation, anti-tube formation, and cell migration assays were used for the valuation of bioactivities of target plant extracts and phytocompounds against angiogenesis. Bioactivity-guided fractionation, HPLC, and various spectral analyses were used to identify active fraction and phytocompounds for anti-angiogenesis. RESULTS: We show that an ethyl acetate (EA) fraction of B. pilosa exhibited significant anti-cell proliferation and anti-tube formation activities against human umbilical vein endothelium cells (HUVEC). Bioassay-guided fractionation led to isolation of one new and one known polyacetylenes, 1,2-dihydroxytrideca-5,7,9,11-tetrayne (1) and 1,3-dihydroxy-6(E)- tetradecene-8,10,12-triyne (2), respectively, from the EA fraction. Compounds 1 and 2 manifested highly specific and significant activities against HUVEC proliferation with IC50 values of 2.5 and 0.375 microg/ml, respectively, however, compound 1 had a more potent effect on preventing tube formation of HUVEC than compound 2 at a dose of 2.5 microg/ml. Western blot analysis showed that both compounds upregulated p27(Kip) or p21(Cip1), cyclin-dependent kinase inhibitors, in HUVEC. CONCLUSIONS: This is the first report to demonstrate that polyacetylenes possess significant anti-angiogenic activities and the ability to regulate the expression of cell cycle mediators, for example, p27(Kip1), p21(Cip1), or cyclin E.  相似文献   
38.
目的:研究柚皮素对人视网膜色素上皮细胞(ARPE-19)和人脐静脉内皮细胞(HUVEC)的抗氧化作用。 方法:采用MTT的方法检测ARPE-19和HUVEC细胞的生存率及增殖率。 结果:3,10mg/L柚皮素能显著增加ARPE-19细胞的增殖率达10.8%和11.4%。10mg/L柚皮素能提高ARPE-19细胞在缺氧,0.3mmol/LNaN,及200μmol/L,H2O2条件下的生存率分别为55.2%,69.2%及50.3%。1mg/L柚皮素能提高ARPE-19细胞在50μmol/L t-BHP和30mg/LNaIO3条件下的生存率达20.2%和30.4%。30mg/L柚皮素能够促进ARPE-19细胞在50μmol/L t-BHP条件下的增殖率达32.2%,而1mg/L柚皮素可以提高30,100,300mg/LNaIO3处理的ARPE-19细胞的增殖率达30.3%,10.3%及18.5%。3,10及30mg/L柚皮素抑制HUVEC的增殖率分别为23.9%,70.4%及77.9%。1,3mg/L柚皮素能提高HUVEC细胞在缺氧条件下的生存率达10.7%和13.1%,以及提高在300mg/LNaIO3条件下的生存率达41.2%和37.7%。3mg/L柚皮素能提高HUVEC细胞在200,400μmol/L H2O2条件下的生存率达20.1%和21.5%. 结论:柚皮素能够促进ARPE-19细胞的增殖率,抑制HU-VEC生长,同时对这两种细胞均有抗氧化作用。因此,柚臾素是治疗老年黄斑变性的很有前景的候选药物。  相似文献   
39.
目的观察冠心病不同阶段患者血清对人脐静脉血管内皮细胞(HUVEC)增殖的影响。方法采集正常健康人群(正常组)、冠心病中高危人群(中高危组)、冠心病急性期患者(急性期组)、冠心病稳定期患者(稳定期组)的血清,分别作用于HUVEC,培养至24、48、72、96h检测吸光度值(OD值)。结果4组血清中加或不加5%胎牛血清,其对HUVEC增殖均有促进作用,正常组、中高危组、急性期组、稳定期组对HUVEC的促增殖作用呈逐渐增强趋势,稳定期组血清促增殖作用最强。结论心血管疾病在急性期后,随着病程和生存期的延长,其血清对HUVEC的促增殖作用逐渐增强。  相似文献   
40.
槲皮素抑制血管生成作用的实验研究   总被引:21,自引:1,他引:21  
目的 研究槲皮素 (Quercetin)对血管生成和培养的人脐静脉内皮细胞 (HUVEC)的影响。方法 采用生长因子 (血管内皮细胞生长因子VEGF、碱性成纤维细胞生长因子bFGF)诱导的鸡胚绒毛尿囊膜 (CAM)血管增生模型观察槲皮素对血管生成的影响 ;利用培养的HUVEC ,用MTT法观察槲皮素抑制内皮细胞增殖的作用 ;流式细胞仪观察槲皮素对HUVEC细胞周期的影响。结果 槲皮素 (0 1、0 0 5和 0 0 2 5mmol·L-1)能明显抑制VEGF诱导的CAM小血管生成 ;槲皮素 (0 1和 0 0 5mmol·L-1)能明显抑制bFGF诱导的CAM小血管生成 ;槲皮素 (2 4 0、12 0 μmol·L-1和 6 0 μmol·L-1)对内皮细胞增殖有抑制作用 ,抑制率分别为 6 7 0 %、5 8 1%和39 7% ;槲皮素 (2 4 0、12 0 μmol·L-1)能显著导致HUVEC的S、G2 期阻滞。结论 槲皮素能抑制VEGF和bFGF诱导的血管生成 ,且对内皮细胞增殖具有抑制作用。  相似文献   
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