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1.
本研究收集健康成人骨髓单个核细胞,用血管内皮生长因子等加以诱导分化,通过荧光显微镜和荧光免疫标记等方法观察和鉴定诱导后的细胞。之后将诱导分化的内皮祖细胞种植到聚氨酯小径人工血管表面,予以15 dyn/cm2的流体切应力处理,并用扫描电镜观察。结果发现外周血单个核细胞诱导分化成为内皮祖细胞,ac- LDL及lectin抗体荧光标记阳性。扫描电镜下,未种植细胞的聚氨酯小径人工血管表面孔径大小比较适合内皮祖细胞爬行;静态种植细胞后,人工血管表面内皮祖细胞排列不整齐;切应力条件下种植细胞后,人工血管表面内皮祖细胞排列较为整齐。因此,在体外能将外周血单个核细胞诱导分化成为内皮祖细胞,内皮祖细胞是小径人工血管内皮化的理想种子细胞。流体切应力对小径聚氨酯人工血管表面内皮祖细胞的生长排列有着良好的机械塑形作用。  相似文献   

2.
血液产生的切应力可以引起血管中的内皮细胞发生生物物理、生化和基因调控水平上的反应,从而调节内皮的结构和功能。当内皮细胞受到的切应力发生变化时,即可引起细胞基因表达上的变化,从而可能引发一些常见的心血管疾病。对切应力调控内皮细胞基因表达机制的研究,有助于找到治疗以上疾病的临床方法。综述了切应力对内皮细胞基因表达的影响及其调控机制,并对其在临床治疗、小口径人工血管构建和药物设计等方面的应用前景进行了展望。  相似文献   

3.
背景:运动条件对内皮祖细胞数量和功能是否会产生的影响目前尚无公识。 目的:观察急性运动对健康成人循环内皮祖细胞数量和功能的影响。 方法:健康男性成人志愿者12例参加急性平板运动锻炼(9.3±2.1) min。用流式细胞仪测定运动前后CD34和KDR双标阳性循环内皮祖细胞水平,ac-LDL及lectin荧光标记方法评估体外培养内皮祖细数量,检测内皮祖细胞的黏附、迁移和增殖能力,并测定运动前后血浆和内皮祖细胞分泌一氧化氮、血管内皮生长因子和粒-巨噬细胞集落刺激因子水平变化。 结果与结论:流式细胞仪检测显示健康志愿者运动后循环内皮祖细胞水平较运动前增加(P < 0.05)。荧光标记法证实运动后ac-LDL及lectin抗体双阳性内皮祖细胞数量较运动前增加(P < 0.05),内皮祖细胞迁移和增殖能力明显增强(P < 0.05),但黏附能力无明显变化。急性运动能明显增加健康志愿者的血浆一氧化氮水平(P < 0.05),健康志愿者运动前后血浆一氧化氮水平和循环内皮祖细胞数量及功能的增加倍数呈明显的直线相关回归关系(P < 0.05)。结果证实,运动可明显增加健康成人循环内皮祖细胞的数量和功能,其机制与其诱导一氧化氮释放增多有关。  相似文献   

4.
背景:内皮祖细胞是外周血中存在的一种干/祖细胞,是成熟内皮细胞的前体细胞,其与氧化应激的关系越来越受到人们的关注,而且国内外研究正日趋增多。 目的:对国内外内皮祖细胞与氧化应激关系的现状及新进展作一综述。 方法:应用计算机检索CNKI和Pubmed数据库中1997-01/2010-05关于内皮祖细胞与氧化应激的文章,在标题和摘要中以“内皮祖细胞,氧化应激”或“endothelial progenitor cells ,oxidative stress”为检索词进行检索。选择文章内容与内皮祖细胞与氧化应激有关者,同一领域文献则选择近期发表或发表在权威杂志文章。初检得到212篇文献,最终选择有代表性的34篇文献进行综述。 结果与结论:内皮祖细胞与氧化应激关系密切,虽然内皮祖细胞具有比成熟内皮细胞更强的抗氧化能力,但在长期氧化应激存在的情况下,氧化应激通过减弱其抗氧化酶的表达,增加氧化酶的表达而促进内皮祖细胞的凋亡而影响其功能及数量,故氧化应激是导致内皮祖细胞数量改变及功能受损的影响因素之一,而通过他汀类药物、血管紧张素转换酶抑制剂/受体拮抗剂及过氧化物酶体激动剂的干预可改善内皮祖细胞的氧化应激状态,保护其功能。  相似文献   

5.
流体切应力作用时间对内皮细胞IL-8 基因表达的影响   总被引:2,自引:6,他引:2  
内皮细胞对力学环境变化敏感,流体切应力可以直接调节内皮细胞基因的表达。为阐明内皮细胞白细胞介素-8(IL-8)基因的表达除受化学因子的调节外还受力学因素的影响,本文用流体切应力(2.23、4.20、6.08dyne/cm^2)处理培养的人脐静脉内皮细胞,然后采用定量RT-PCR的方法检测内皮细胞IL-8基因的表达情况。结果显示:未用切应力处理的内皮细胞没有IL-8基因的表达;切应力处理内皮细胞后,1h IL-8mRNA表达增加,2hIL-8mRNA表达量至最高值,3hIL-8mRNA表达量开始下降,4h后IL-8mRNA持续低表达;各实验组(2.23、4.20、6.08dyne/cm^2)均表现出相同的IL-8mRNA随时间的变化规律。提示流体切应力确可诱导内皮细胞表达IL-8,而且IL-8的表达量与切应力作用时间有关,呈双相性变化。流体切应力诱导内皮细胞表达IL-8,可能在急性炎症和动脉粥样硬化的发生、发展过程中具有重要作用。  相似文献   

6.
流体切应力强度对内皮细胞IL-8基因表达的影响   总被引:4,自引:1,他引:4  
内皮细胞位于血流与血管之间,内皮细胞调控的机械力相关反应已成为正常血管反应的一部分。切应力在调节内皮细胞功能上具有重要作用。流体切应力可以直接调节内皮细胞基因的表达,其中包括诱导内皮细胞表达IL-8,而且IL-8的表达量与切应力作用时间有关。 为阐明内皮细胞IL-8基因的表达除了与切应力的作用时间有关外还与切应力的强度有关,我们用不同强度的流体切应力(2.23、4.20、6.08、8.19、9.67、12.15、14.40、16.87、19.29dyne/cm^2)处理培养的人脐静脉内皮细胞,然后采用定量RT-PCR的方法检测内皮细胞IL-8 基因的表达情况。结果显示:未用切应力处理的内皮细胞没有IL-8基因的表达,切应力处理内皮细胞后,低切应力(2.23dyne/cm^2)时IL-8mRNA表达量明显增加为高切应力(19.29dyne/cm^2)时IL-8mRNA表达量的约68(作用1小h)或52倍(作用2h)。IL-8mRNA的表达量与内皮细胞所施加的切应务强度呈反变关系,直线回归方程,1h时为y=7.57-0.11x,相关系数r=7.97;2h时为y=7.92-0.10x,相关系数r=0.96。式中:y为切应力作用下内皮细胞IL-8mRNA的表达量(拷贝数的对数值);x为施加于内皮细胞的切应力强度(dyna/cm^2)。不同的切应力作用时间(1h,2h)均表现出相同的IL-8mRNA随切应力强度的变化规律。提示流体应力诱导内皮细胞表达IL-8,不仅与切应力的作用时间有关,而且IL-8的表达量与切应力强度有关。流体切应诱导内皮细胞IL-8mRNA的表达急剧增高,可能在炎症机制和动脉粥样硬化的发生、发展过程中具有重要作用。  相似文献   

7.
目的 研究流体剪切应力处理对晚期内皮祖细胞(endothelial progenitor cells,EPCs)体外及体内生物学功能的影响。 方法 密度梯度离心法分离大鼠骨髓单核细胞,应用EGM-2MV进行体外培养。以3~4代的EPCs,即晚期EPCs为靶细胞,对其施以1.2 Pa剪切应力处理。采用EdU标记技术、黏附能力测定实验、改良的Boyden小室、Annexin V/PI、β 半乳糖苷酶检测法、Matrigel法、荧光定量RT PCR等方法分别检测剪切应力对晚期EPCs增殖、黏附、迁移、凋亡、衰老、体外成血管及VEGF mRNA表达等生物学功能的影响。应用大鼠颈动脉损伤模型及细胞原位移植等实验手段检测剪切应力预处理对晚期EPCs修复受损内皮的影响。结果1.2 Pa剪切应力处理可不同程度提高晚期EPCs的增殖、黏附、迁移及成血管能力(P<0.01),上调VEGF的基因表达,抑制晚期EPCs的衰老及凋亡(P<0.01);移植经剪切应力预处理的晚期EPCs可加速损伤内皮的修复,减缓内膜的增生。结论 流体剪切应力可改善晚期EPCs的功能活性,提高晚期EPCs修复损伤血管内皮的能力, 这为EPCs的临床应用及剪切应力介导的细胞疗法提供了实验依据。  相似文献   

8.
利用pUC 8为载体质粒,将合成的人Cu/Zn SOD基因置于Lac Z启动子的调控下,构建了含有该基因的表达质粒pCZS Ⅰ。首次成功地在大肠杆菌中表达了合成人Cu/Zn SOD的基因。SDS聚丙烯酰胺凝胶电泳薄层扫描分析证明,SOD基因的表达产物占细胞可溶性蛋白质的13%左右,用光扩增法捡测表达产物的酶活性,每毫克蛋白质为48.6 McCord Fridovich单位。  相似文献   

9.
血管内皮祖细胞(EPCs)是内皮细胞的前体细胞,特异性表达CD34,CD133和VEGFR-2,具有向血管内皮细胞分化的潜能。EPCs主要位于骨髓和外周血。肿瘤的生长和转移依赖于肿瘤血管新生。肿瘤细胞可合成和释放多种细胞因子,在不同因子的趋化作用下EPCs从骨髓动员至外周血循环,然后迁移和定居到肿瘤组织,经细胞因子诱导分化为成熟内皮细胞,参与肿瘤血管新生。VEGF/VEGFR-2信号途径在EPCs参与的肿瘤血管新生方面起重要作用。  相似文献   

10.
内皮祖细胞与氧化应激   总被引:6,自引:0,他引:6  
内皮祖细胞(endothelial progenitor cells,EPCs)是成熟内皮细胞的前体细胞,参与损伤组织的血管新生和再内皮化。研究表明,氧化应激能引起EPCs的数量减少和功能减弱。虽然EPCs存在抗氧化酶系统,但是当细胞正常的氧化还原稳态失衡时,活性氧过度产生而聚积,引起氧化应激,导致细胞的衰老或凋亡。  相似文献   

11.
BACKGROUND: The present study was undertaken to investigate the cAMP-dependent regulation of copper-zinc superoxide dismutase (Cu,Zn-SOD) and manganese SOD (Mn-SOD) by ovarian steroids in human endometrial stromal cells (ESC). METHODS and RESULTS: To examine the effect of cAMP on SOD expression, ESC were incubated with dibutyryl-cAMP (db-cAMP, 0.5 mmol/l), forskolin (25 micromol/l), or estradiol (E(2), 10(-8) mol/l) + medroxyprogesterone acetate (MPA, 10(-6) mol/l), for 18 days. E(2) + MPA significantly increased Cu,Zn-SOD activity and mRNA concentrations, whereas db-cAMP and forskolin had no effect. On the other hand, Mn-SOD activity and mRNA concentration were significantly increased by all of these treatments. Insulin-like growth factor-binding protein-1, a marker of decidualization, was clearly induced by db-cAMP, forskolin or E(2) + MPA, accompanied by morphological changes characteristic of decidualization. To study whether the increase in Mn-SOD by db-cAMP or E(2) + MPA was mediated by cAMP-dependent protein kinase A (PKA), ESC were incubated with protein kinase inhibitor (PKI) (10 microg/ml), an inhibitor of PKA, in the presence of db-cAMP or E(2) + MPA. The increase in Mn-SOD activity following db-cAMP or E(2) + MPA was completely inhibited by PKI. CONCLUSIONS: In the process of decidualization, E(2) + MPA increases Mn-SOD expression via a cAMP-dependent pathway. Cu,Zn-SOD is also up-regulated by E(2) + MPA, but via a different pathway from that involving cAMP.  相似文献   

12.
The present study was undertaken to investigate the role of estrogen and progesterone in the expression of copper-zinc superoxide dismutase (Cu,Zn-SOD) and manganese SOD (Mn-SOD) in human endometrial stromal cells (ESC). ESC were incubated with estradiol (10(-8) mol/l), medroxyprogesterone acetate (MPA, 10(-6) mol/l), or estradiol + MPA for 18 days. MPA significantly increased Cu,Zn-SOD and Mn-SOD mRNA levels and enzyme activities as well as the mRNA level of insulin-like growth factor-binding protein-1 (IGFBP-1), a marker for decidualization. Estradiol only augmented the effects of MPA on Cu,Zn-SOD activity and IGFBP-1 mRNA level, and estradiol alone had no effect. To study the withdrawal of estrogen and progesterone (EP withdrawal), ESC that had been treated with estradiol + MPA for 12 days were washed and then incubated with or without estradiol + MPA for a further 11 days. Cu,Zn-SOD mRNA levels and activities declined after EP withdrawal, while they were gradually increased by the continuous treatment with estradiol + MPA. In contrast, Mn-SOD mRNA levels and activities were not affected by EP withdrawal. IGFBP-1 mRNA levels were significantly increased 4 days after EP withdrawal and decreased thereafter, whereas they were gradually increased by the continuous treatment with estradiol + MPA. In conclusion, Cu,Zn-SOD, Mn-SOD and IGFBP-1 are differently regulated by estrogen and progesterone in human ESC. The decrease in Cu,Zn-SOD after the ovarian steroid withdrawal may be involved in endometrial breakdown.  相似文献   

13.
The myocardium in 50 autopsy cases was studied using immunostaining for copper-zinc superoxide dismutase (CuZn-SOD) and standard histochemical procedures. Mucinous degeneration observed in 42 cases showed moderately enhanced expression of immunoreactive CuZn-SOD in lesions which were stained strongly by periodic acid-Schiff but negative with Heidenhain iron-hematoxylin (HIH), von Kossa and luxol fast blue (LFB) stains, whereas coagulation necrosis in 4 cases revealed almost identical immunostaining for CuZn-SOD and HIH to that of contraction band necrosis, i.e. strongly positive HIH staining but negative immunostaining. Basophilic alteration of the myocardial cells in sections fixed with 4% formalin in 2% calcium acetate was seen in 29 cases, being identified frequently in isolated cells as well as in several foci varying considerably in size. This type of alteration demonstrated significantly enhanced expression of immunoreactive CuZn-SOD and was strongly positive with von Kossa and LFB stains. The present study indicates that the myocardium can be affected by free radicals produced in any organ of the body, and that subsequently, insoluble phospholipids react with calcium ions in the fixative and accumulate in the basophilic sarcoplasm.  相似文献   

14.
Human endothelial cells infected with Rickettsia rickettsii, the etiological agent of Rocky Mountain spotted fever, undergo striking morphological changes to the endoplasmic reticulum-outer nuclear envelope complex. These changes are accompanied by concurrent accumulation of intracellular peroxides. Both of these findings are consistent with the notion that cells undergo some form of oxidative stress. Since oxidant injury is often initiated or mediated through oxygen radicals, we examined superoxide radical generation when endothelial cells were exposed to R. rickettsii. We also examined the levels of superoxide dismutase, an enzyme induced in response to increased superoxide formation. The levels of both superoxide and superoxide dismutase increased when endothelial cells were exposed to R. rickettsii. These results, together with our previous findings, support our hypothesis that cells infected by this intracellular bacterium experience oxidant-mediated injury that may eventually contribute to cell death.  相似文献   

15.
Immunoelectron microscopy and cellular fractionation on sucrose density gradients have been used to examine the intracellular distribution of copper-zinc superoxide dismutase (SOD) in the canine and rat endocrine pancreas. Using rabbit anti-canine copper-zinc SOD as the primary antiserum, immunostaining in canine beta and non-beta islet cells was significantly greater than that in serial sections of the same islet incubated with preimmune serum from the same rabbit. Within the cells, immunostaining was associated with spherical and crystalloid granules as well as with the cytoplasm. Radioimmune assays of cellular fractions or rat islet-cell preparations showed that the granule-rich fraction containing large amounts of insulin was also rich in SOD. This interesting observation of association of SOD with hormone-containing granules suggests that SOD may play a role in protecting these oxidation-sensitive proteins.  相似文献   

16.
 目的:本研究目的是阐明血流剪切应力抑制血管内皮细胞凋亡的分子机制。方法: 人脐静脉内皮细胞(HUVECs)培养于DMEM, 当细胞融合时,转染Smac基因,将细胞暴露于20 dyne/cm2 的剪切应力,分别测定人类凋亡蛋白抑制剂(human inhibitor of apoptosis protein-2, HIAP-2) 蛋白表达及细胞凋亡蛋白酶(caspase-3)活性。 结果: 20 dyne/cm2 的剪切应力抑制caspase-3活性的增加,此作用与剪切应力能够明显诱导内皮细胞产生HIAP-2 蛋白表达明显增加有关。 结论:证实生理水平剪切应力能够明显诱导内皮细胞产生HIAP-2 蛋白的表达,这可能是剪切应力抑制内皮细胞凋亡发挥抗动脉粥样硬化作用的机制之一。  相似文献   

17.
Summary Copper-zinc superoxide dismutase (CuZn-SOD) has been localized in formalin-fixed, paraffin-embedded sections of both canine and rat brains. Staining with an immunoenzyme bridge sequence revealed CuZn-SOD in all regions of the brains examined. Specific sites of localization included cerebral cortical pyramidal cells, cerebellar Purkinje cells, neurons in subcortical nuclei, and oligodendrocytes throughout the brain. Similar sites of CuZn-SOD localization were identified in both species. These results are compared with reports by various investigators of SOD bioactivity in the brain.  相似文献   

18.
The cellular localization of copper-zinc superoxide dismutase (CuZn SOD) mRNA was determined in the human hippocampus by in situ hybridization with a 35S-labelled DNA probe complementary to human CuZn SOD mRNA. A positive hybridization signal was detected in pyramidal cell layers CA1-CA4 of Ammon's horn (CA), pyramidal cells of subiculum and in the granule cells of the dentate gyrus. The fact that CuZn SOD gene expression is important in neurones which are preferentially vulnerable in neurodegenerative processes such as Alzheimer's disease, suggests a role played by oxygen free radicals in the mechanism of nerve cell death.  相似文献   

19.
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