内皮源性舒张因子对内皮损伤的大鼠胸主动脉中血管紧张素Ⅱ的影响

利用放免测定法在大鼠胸主动脉内皮损伤内膜增生模型上观察了内皮源性舒张因子（ＥＤＲＦ）的前体Ｌ－Ａｒｇ和抑制剂ＬＮＮＡ对内皮损伤血管局部ｃＧＭＰ（ＥＤＲＦ的效应物）和Ａｇ－Ⅱ水平的影响。结果发现,动脉血管内皮损伤后,其ｃＧＭＰ含量显著下降,血管局部Ａｇ－Ⅱ水平明显上升;ＬＮＮＡ可使这一现象更加明显;而Ｌ－Ａｒｇ却可使内皮损伤动脉中下降的ｃＧＭＰ明显上升,使其升高的局部Ａｇ－Ⅱ水平明显下降。表明ＥＤＲＦ可通过ｃＧＭＰ途径抑制内皮损伤的动脉中Ａｇ－Ⅱ的产生。     

人参皂甙对气虚型大鼠血管内皮损伤相关基因谱的影响

用高L-蛋氨酸复制SD大鼠血管内皮损伤,并附以负重游泳法制造气虚实验模型。应用RT-PCR技术和NCB I提供的SAGE(serial analysis of gene expression)数据库及在线工具,分析内皮损伤相关的炎症、氧化应激基因表达谱的变化,以及人参皂甙对基因表达谱的影响。结果显示,与模型组相比,人参皂甙组炎症相关COX-1(P<0.001)、COX-2(P<0.001)、氧化应激相关iNOS(P<0.001)、SOD基因表达(P<0.05)及血管舒缩相关eNOS(P<0.05)、ECE(P<0.001)的基因表达降低;PCS的基因表达变化无统计学意义。人参皂甙能够改善气虚型大鼠血管内皮损伤病变时基因表达谱的异常,从而起到保护血管内皮免受损伤的作用。探讨人参皂甙对气虚型大鼠血管内皮损伤相关的炎症、氧化应激等基因表达谱的影响。     

缺血再灌后血管内皮空泡的形成与内皮的损伤

目的：在活体上探讨缺血再灌后血灌内上细胞损伤及白细胞、血小板与内皮之间粘附的变化。方法：用失血及与再回输血液造成缺血再灌流模型,在高倍显微镜下观察肠系膜微血管内皮损伤及血细胞粘附的变化。结果：缺血再灌后1－3h细静脉、集合毛细血管内出现白细胞、血小板的粘附,血管内皮水肿、管壁增厚,有的血管内皮细胞的胞浆形成圆丘形的空泡,空泡从血管内皮突入管胺、空泡直径10－30μm多出现的细动脉内,在同一根血管内可同时出现几个空泡,大的空泡几科占据血管腔的2／3。结论：缺血再灌后血管内皮水肿及空泡形成,显示内皮细胞的严重损伤。     

血管内皮生长因子基因对兔髂动脉内膜损伤的组织形态变化过程的影响

探讨血管内皮细胞的特异丝裂原－血管内皮生长因子（VEGF）基因阻止血管内膜损伤后形成再狭窄的组织变化过程。建立球囊拉伤血管内膜的兔髂动脉模型,将携带VEGF目的基因的真核表达载体pcDNA3/VEGF经多聚赖氨酸处理的PTCA球囊导管导入拉伤的血管内膜。VEGF基因组拉伤2周时血管内壁有VEGF mRNA和蛋白的高表达。血管内膜内皮化较快。2周时即有许多血管内皮细胞呈岛状分布。4周时内膜基本恢复光滑。内膜平滑肌细胞增生明显减少,而对照组2周时血管内膜粗糙,基底膜暴露,拉伤后4周仍无内皮细胞再生,最后形成虫蚀样改变。血管中膜平滑肌细胞穿过内弹性膜进入内膜并大量增生,内膜增厚。VEGF基因定位导入血管内壁后。VEGF mRNA和蛋白高表达且发挥其生物学效应,内皮细胞岛状增生,加快内膜内皮化,减轻内膜增厚。     

虫草素对慢性肾脏病大鼠血管内皮损伤的保护作用及其机制

摘要 目的：探讨虫草素对慢性肾脏病(chronic kidney disease,CKD)大鼠血管内皮损伤的保护作用及其机制。方法：慢性肾脏病大鼠(n=48)随机平分为四组-模型组、虫草素高剂量组、虫草素中剂量组、虫草素低剂量组,虫草素高剂量组、虫草素中剂量组、虫草素低剂量组,分别给予虫草素160 mg/kg、80 mg/kg、40 mg/kg,模型组灌胃给予等量生理盐水,每天1次,连续给药治疗2周。结果：虫草素高剂量组、虫草素中剂量组、虫草素低剂量组治疗1周、治疗2周的24 h尿量、血清尿素氮(blood urea nitrogen,BUN)与肌酐(serum creatinine,Scr)水平都低于模型组(P<0.05),体重都高于模型组(P<0.05),不同剂量组别之间对比差异也有统计学意义(P<0.05)。虫草素高剂量组、虫草素中剂量组、虫草素低剂量组治疗2周的结缔组织生长因子(Connective tissue growth factor,CTGF)、血管内皮生长因子(Vascular endothelial growth factor,VEGF)蛋白相对表达水平高于模型组(P<0.05),肾小球硬化指数、肾小管损伤评分都低于模型组(P<0.05),不同剂量组别之间对比差异也有统计学意义(P<0.05)。结论：虫草素在慢性肾脏病大鼠的应用能发挥血管内皮损伤保护作用,促进改善大鼠的肾功能,提高大鼠的体重,且具有剂量依赖性。     

血管内皮生长因子

血管内皮生长因子叶正茂,周爱儒（北京医科大学生化与分子生物学系,北京１０００８３）关键词血管内皮生长因子,血管通透因子,血管生成血管内皮生长因子（ＶＥＧＦ,ｖａｓｃｕｌａｒｅｎｄｏｔｈｅｌｉａｌｇｒｏｗｔｈｆａｃｔｏｒ）又称血管通透因子（ｖａｓｃｕｌ...     

人参皂甙对气虚型血管损伤中COX-2和iNOS相互作用的影响

探讨气虚型大鼠血管内皮损伤中COX-2和iNOS的蛋白水平及其相互作用,以及人参皂甙的防治作用.用高L-蛋氨酸复制SD大鼠血管内皮损伤,并附以负重游泳法制造气虚实验模型.应用Western blotting分析内皮损伤相关的COX-2和iNOS蛋白水平的变化,免疫共沉淀和激光共聚焦显微镜技术,探讨两者的相互作用,光镜和电镜分析血管内皮的病理变化.结果显示:模型组、COX-2和iNOS蛋白含量显著增高,并存在明显的相互作用,与血管内皮的病理损伤相一致;与模型组相比,人参皂甙组COX-2和iNOS的蛋白含量降低,且两者的相互作用减弱.气虚型大鼠血管内皮损伤中,COX-2和iNOS蛋白含量增高,且两者之间的相互作用增强,加重血管内皮损伤,人参皂甙能够纠正这些异常,起到保护血管内皮免受损伤的作用.     

早期血管内皮功能障碍检测方法的评价

血管内皮功能障碍是心血管疾病的主要危险因素之一,早期准确评价这一器官功能很有临床价值.目前临床检测方法主要有以下三种方法:血浆中释放血浆标志物、通过影像学检测血管舒张功能、循环内皮相关细胞计数.三种方法各有优缺点,并且它们之间是相互联系.本文就此三种方法的研究进展做一概述.     

血管内皮生长因子受体3在大鼠胚胎皮肤淋巴管和血管内皮的表达及意义

目的观察血管内皮生长因子受体3(vascular endothelial growth factor receptor-3, VEGFR-3)蛋白在大鼠第15d胚胎和第21d胚胎皮肤淋巴管和血管内皮的表达水平,探讨VEGFR-3在胚胎淋巴管和血管发生发育中的生物功能.方法应用免疫组织化学技术(SABC法)对大鼠第15d和第21d胚胎共61例皮肤样本进行抗鼠VEGFR-3免疫组织化学染色,观察VEGFR-3在皮肤淋巴管和血管内皮细胞的表达情况.结果大鼠胚胎皮肤淋巴管和血管内皮细胞均阳性表达VEGFR-3蛋白,VEGFR-3蛋白在大鼠胚胎第15d、胚胎第21d皮肤淋巴管内皮细胞的阳性表达率分别是38.71%(12/31)和73.33%(22/30),第21d胚胎皮肤淋巴管VEGFR-3蛋白的表达水平明显高于第15d胚胎皮肤淋巴管VEGFR-3蛋白的表达水平(P<0.01).VEGFR-3蛋白在大鼠胚胎第15d、胚胎第21d皮肤血管内皮细胞的阳性表达率分别是48.39%(15/31)和46.67%(14/30),第15d和第 21d胚胎皮肤血管VEGFR-3蛋白的表达水平之间无明显差异(P>0.05).结论随着大鼠胚胎的发育,VEGFR-3蛋白在皮肤淋巴管的表达水平表现为明显上升的趋势,提示VEGFR-3在淋巴管发生发育中的作用逐渐增强.     

Increased endothelial and vascular smooth muscle cell adhesion on nanostructured titanium and CoCrMo

In the body, vascular cells continuously interact with tissues that possess nanostructured surface features due to the presence of proteins (such as collagen and elastin) embedded in the vascular wall. Despite this fact, vascular stents intended to restore blood flow do not have nanoscale surface features but rather are smooth at the nanoscale. As the first step towards creating the next generation of vascular stent materials, the objective of this in vitro study was to investigate vascular cell (specifically, endothelial, and vascular smooth muscle cell) adhesion on nanostructured compared with conventional commercially pure (cp) Ti and CoCrMo. Nanostructured cp Ti and CoCrMo compacts were created by separately utilizing either constituent cp Ti or CoCrMo nanoparticles as opposed to conventional micron-sized particles. Results of this study showed for the first time increased endothelial and vascular smooth muscle cell adhesion on nanostructured compared with conventional cp Ti and CoCrMo after 4 hours' adhesion. Moreover, compared with their respective conventional counterparts, the ratio of endothelial to vascular smooth muscle cells increased on nanostructured cp Ti and CoCrMo. In addition, endothelial and vascular smooth muscle cells had a better spread morphology on the nanostructured metals compared with conventional metals. Overall, vascular cell adhesion was better on CoCrMo than on cp Ti. Results of surface characterization studies demonstrated similar chemistry but significantly greater root-mean-square (rms) surface roughness as measured by atomic force microscopy (AFM) for nanostructured compared with respective conventional metals. For these reasons, results from the present in vitro study provided evidence that vascular stents composed of nanometer compared with micron-sized metal particles (specifically, either cp Ti or CoCrMo) may invoke cellular responses promising for improved vascular stent applications.     

Culture of endothelial cells by transfection with plasmid harboring vascular endothelial growth factor

Vascular endothelial cells (ECs) are usually difficult to culture in a large scale because of their complicated requirements for cell growth. As the vascular endothelial growth factor (VEGF) is a key growth factor in the EC culture, we transfected human umbilical vein endothelial cells (HUVEC) using a plasmid containing VEGF gene and let them grow in a culture medium eliminated an important supplement, endothelail cell growth supplement (ECGS). The expression of VEGF by HUVEC tansfected with VEGF gene was not enough to stimulate the growth of HUVEC, only 40% of maximum cell density obtainable in the presence of ECGS., However, when the culture medium was supplied with 2.5 ng/mL of basic fibroblast growth factor (bFGF), a synergistic effect of VEGF and bFGF was observed. In this case, the final cell density was recovered up to about 78% of maxium value.     

Identification of peptides inhibiting adhesion of monocytes to the injured vascular endothelial cells through phage-displaying screening

Using oxidized low-density lipoprotein (LDL)-injured vascular endothelial cells (ECs) as target cells, peptides specifically binding to the injured ECs were screened from a phage-displaying peptide library by using the whole-cell screening technique after three cycles of the ““““““““““““““““““““““““““““““““““““““““““““““““““““““““““““““““adsorption-elution-amplification““““““““““““““““““““““““““““““““““““““““““““““““““““““““““““““““ procedure. Positive phage clones were identified by ELISA, and the inserted amino acid sequences in the displaying peptides were deduced from confirmation with DNA sequencing. The adhesion rate of ECs to monocytes was evaluated by cell counting. The activity of endothelial nitric oxide synthase (eNOS), and the expression levels of caveolin-1 and intercellular adhesion molecule-1 (ICAM-1) were determined by Western blotting. Six positive clones specifically binding to injured ECV304 endothelial cells were selected from fourteen clones. Interestingly, four phages had peptides with tandem leucine, and two of these even shared an identical sequence. Functional analysis demonstrated that the YCPRYVRRKLENELLVL peptide shared by two clones inhibited the expression of ICAM-1, increased nitric oxide concentration in the culture media, and upregulated the expression of caveolin- 1 and eNOS. As a result, the adhesion rate of monocytes to ECV304 cells was significantly reduced by 12.1%. These data suggest that the anti-adhesion effect of these novel peptides is related to the regulation of the caveolin- 1/nitric oxide signal transduction pathway, and could be of use in potential therapeutic agents against certain cardiovascular diseases initiated by vascular endothelial cell damage.     

p38丝裂原素激活的蛋白激酶在调节低氧诱导人内皮细胞分泌血管内皮生长因子过程中的作用

血管内皮细胞中血管内皮生长因子(vascular endothelial growthfactor,VEGF)的合成增加在促进血管新生的过程中起着非常重要的作用.然而低氧诱导VEGF分泌的细胞内信号转导机制还不是很清楚.人脐静脉内皮细胞系(ECV304)在低氧或常氧的状态下培养12～24 h后分别用实时定量PCR和Western blot的方法来检测VEGF mRNA的表达及ERK1/2和p38激酶的磷酸化水平.分泌到培养液中的VEGF蛋白用酶联免疫吸附(ELISA)的方法来检测.业已报道,ERK的抑制剂PD98059能够抑制低氧诱导的VEGF基因的表达,根据这个报道,我们发现在低氧情况下,ECV304细胞的ERK1/2磷酸化水平增高以及VEGF的合成增加等这些变化也能被PD98059所抑制.本次实验的新发现是p38激酶的激活在低氧诱导VEGF合成增加中的作用.p38激酶的抑制剂SB202190能抑制低氧诱导的VEGF合成增加.这些数据首次直接证实了p38激酶在低氧诱导人内皮细胞分泌VEGF增加过程中的作用.     

藏药红景天减弱高原肺动脉高压大鼠肺小血管病理变化和血管内皮生长因子的增高

本研究旨在观察藏药红景天对高原自然环境下建立的肺动脉高压大鼠模型中肺血管重构和血管内皮生长因子(vascu-1ar endothelial growth factor,VEGF)表达的影响,探讨其对高原肺动脉高压的防治作用与机制.健康雄性Wistar大鼠50只,随机分为平原对照组、高原10天组、高原30天组、红景天10...     

S-adenosyl methionine prevents endothelial dysfunction by inducing heme oxygenase-1 in vascular endothelial cells

S-adenosyl methionine (SAM) is a key intermediate in the metabolism of sulfur amino acids and is a major methyl donor in the cell. Although the low plasma level of SAM has been associated with atherosclerosis, the effect of SAM administration on atherosclerosis is not known. Endothelial dysfunction is an early prerequisite for atherosclerosis. This study was undertaken to investigate the possible preventive effect of SAM on endothelial dysfunction and the molecular mechanism of its action. SAM treatment prevented endothelial dysfunction in high fat diet (HFD)-fed rats. In cultured human aortic endothelial cells, linoleic acid (LA) increased and SAM decreased cell apoptosis and endoplasmic reticulum stress. Both LA and SAM increased heme oxygenase-1 (HO-1) expression in an NF-E2-related factor 2-dependent manner. However, knockdown of HO-1 reversed only the SAM-induced preventive effect of cell apoptosis. The LA-induced HO-1 expression was dependent on PPARα, whereas SAM induced HO-1 in a PPAR-independent manner. These data demonstrate that SAM treatment prevents endothelial dysfunction in HFDfed animals by inducing HO-1 in vascular endothelial cells. In cultured endothelial cells, SAM-induced HO-1 was responsible for the observed prevention of cell apoptosis. We propose that SAM treatment may represent a new therapeutic strategy for atherosclerosis.     

Localized cysteine sulfenic acid formation by vascular endothelial growth factor: role in endothelial cell migration and angiogenesis

Abstract

Reactive oxygen species (ROS) are important mediators for VEGF receptor 2 (VEGFR2) signalling involved in angiogenesis. The initial product of Cys oxidation, cysteine sulfenic acid (Cys-OH), is a key intermediate in redox signal transduction; however, its role in VEGF signalling is unknown. We have previously demonstrated IQGAP1 as a VEGFR2 binding scaffold protein involved in ROS-dependent EC migration and post-ischemic angiogenesis. Using a biotin-labelled Cys-OH trapping reagent, we show that VEGF increases protein-Cys-OH formation at the lamellipodial leading edge where it co-localizes with NADPH oxidase and IQGAP1 in migrating ECs, which is prevented by IQGAP1 siRNA or trapping of Cys-OH with dimedone. VEGF increases IQGAP1-Cys-OH formation, which is prevented by N-acetyl cysteine or dimedone, which inhibits VEGF-induced EC migration and capillary network formation. In vivo, hindlimb ischemia in mice increases Cys-OH formation in small vessels and IQGAP1 in ischemic tissues. In summary, VEGF stimulates localized formation of Cys-OH-IQGAP1 at the leading edge, thereby promoting directional EC migration, which may contribute to post-natal angiogenesis in vivo. Thus, targeting Cys-oxidized proteins at specific compartments may be the potential therapeutic strategy for various angiogenesis-dependent diseases.     

金属硫蛋白拮抗同型半胱氨酸对血管内皮细胞的脂质过氧化作用

目的:观察金属硫蛋白(metallothionein,MT)对同型半胱氨酸(homocysteine Hcy)损伤血管内皮细胞的拮抗作用及机制.方法:培养液中分别加入Hcy及Hcy MT孵育血管内皮细胞,自动生化分析仪测培养液乳酸脱氢酶(LDH)活性,硫代巴比妥酸法测细胞丙二醛(MDA)含量.结果:同型半胱氨酸增加内皮细胞LDH及蛋白漏出,并使细胞MDA含量明显升高.MT呈浓度依赖性地抑制Hcy所致的血管内皮细胞损伤及MDA增高.结论:MT拮抗Hcy对血管内皮细胞的脂质过氧化损伤.