银杏叶提取物对牛主动脉内皮细胞通透性的影响

目的:考察正常和缺氧状态下银杏叶提取物(Egb761)对VEGF引起体外培养牛主动脉内皮细胞(BAEC)脂蛋白通透性改变的影响.方法:将VEGF及Egb761加入BAEC共孵育,用SN-695型液闪计数器测[125I]氧化低密度脂蛋白([125I]OxLDL)通过BAEC的百分率.结果:VEGF可剂量依赖性地增强BAEC对[125I]OxLDL的通透性(P＜0.01),缺氧3h可促进VEGF所致的的通透性增加.Egb761能显著抑制VEGF诱导的通透性升高(P＜0.01).结论:Egb761对缺氧状态下VEGF诱导血管内皮通透性升高有显著的抑制作用.     

缺氧对血管内皮生长因子诱导牛冠状动脉内皮细胞脂蛋白通透性升高的调控及丹酚酸B的抑制作用

目的　为了了解缺氧对血管内皮生长因子(VEGF)增强血管内皮细胞通透性作用的影响及其与动脉粥样硬化的关系 ,考察了正常和缺氧状态下VEGF对体外培养牛冠状动脉内皮细胞 (BCEC)脂蛋白通透性的影响及丹酚酸B的抑制作用。方法　正常及缺氧条件下 ,将VEGF及丹酚酸B加入BCEC共孵育 ,用SN 695型液闪计数器测 [12 5I]低密度脂蛋白([12 5I]LDL)通过BCEC的百分率。结果　VEGF可显著增强BCEC对 [12 5I]LDL的通透性 ,这种增加具有浓度依赖性。缺氧 3h可促进VEGF所致的的通透性增加。丹酚酸B在正常和缺氧条件下均显著抑制VEGF诱导的BCEC通透性升高。结论　VEGF可增强血管内皮细胞的通透性 ,可能在动脉粥样硬化的形成和发展过程中起一定作用。丹酚酸B对VEGF诱导的血管内皮通透性升高有显著的抑制作用     

血管内皮生长因子的研究进展

198 3年,Senger等发现一种可使豚鼠皮肤血管通透性增高的因子,称其为血管通透性因子(VPF)。1989年,Gospodarow等从牛垂体滤泡中分离纯化得到一种蛋白质,能特异作用于血管内皮细胞,引起血管内皮细胞增生,并在体内诱导血管形成,遂命名为血管内皮生长因子(vascularendothelial gro     

血管内皮生长因子在缺氧缺血性脑损伤中作用的研究进展

血管内皮生长因子（vascular endothelial growth factor，VEGF）又称血管通透因子（vascular permeability factor，VPF），是由两个亚基间通过二硫键连接形成的同源二聚体糖蛋白，相对分子量为34-45KD。人的VEGF基因位于6号染色体Gp21．3，全长14kb，包括8外显子、7个内含子，至少以6种亚型存在，分别为VEGF111、VEGF145、VEGF165、VEGF183、VEGF189、VEGF206。VEGF121、VEGF145、VEGF165，是分泌型可溶蛋白，具有增加内皮细胞的通透性、促进血管内皮细胞有丝分裂作用，当各种原因引起表达增加时可在血清中测出。而其余亚型的VEGF与细胞结合的形式存在，以结合形式存在的VEGF仅能增加血管内皮的通透性，在血清中难以测出。VEGF可在正常成人和动物组织中表达，但一般水平很低。     

血管内皮生长因子基因对内皮细胞功能的影响

目的观察携带VEGF基因的腺病毒在成功转染内皮细胞后,转染的VEGF基因对内皮细胞功能的影响。方法用携带VEGF165腺病毒转染内皮细胞,分成VEGF,空病毒,PTK787及对照组,分别用ELIsA法检测细胞培养上清中的t-PA蛋白的含量,观察其对内皮细胞分泌t-PA蛋白的影响。结果携带VEGF165腺病毒人工血管促进内皮细胞分泌t-PA蛋白,而添加了PTK787组则显著抑制蛋白分泌,与对照组相比均有显著性差异（P〈0．05）。结论证实了携带含VEGF基因腺病毒可以转染内皮细胞并对内皮细胞的分泌功能产生影响。     

血管内皮生长因子

血管内皮生长因子是一类能够特异地作用于血管内皮细胞,通过特异性受体发挥生物学作用的血管生长调控因子。促进内皮细胞增生;增加细胞质钙离子浓度;增加血管渗透性,改变细胞外基质,促进血管生成,其中一些因子还在淋巴管生成中起作用。本文对血管内皮生长因子的特征、生物学作用等进行了综述。     

血管内皮生长因子165诱导人血管内皮细胞多药耐药表型

目的：研究血管内皮生长因子165（VEGF165）对血管内皮细胞药物敏感性的影响。方法：人真皮微血管内皮细胞（HDMEC）与抗癌药物和VEGF165混合培养,MTT法分析药敏变化,琼脂糖电泳检测细胞凋亡,RT-PCR、免疫印迹法分析HDMEC产生多药耐药表型的机制。结果：VEGF165体外诱导HDMEC对多种抗癌药物耐药,如表柔比星、顺铂、足叶乙甙、丝裂霉素C、长春新碱、CPT-11、泰素等,其机制与VEGF165诱导HDMEC上调表达多药耐药相关蛋白和肺耐药相关蛋以及下调表达Bax蛋白有关。结论：VEGF165诱导血管内皮细胞的多药耐药表型,提示化疗时抗癌药物的抗血管生成活性可能取决于肿瘤微环境。     

血管内皮生长因子对兔肾血管内皮细胞体外培养的影响

目的 探索血管内皮生长因子（VEGF）对兔肾血管内皮细胞（MVECs）体外培养的影响。方法采用三步梯度筛网法,获得纯度较高的肾血管球,0．5％胶原酶Ⅳ37℃消化15～20min,离心沉淀获取血管内皮细胞,分加与不加VEGF培养。对培养的细胞用倒置显微镜观察常规形态,用免疫组化法进行第Ⅷ因子相关抗原鉴定,用透射电镜观察细胞浆Weibel-Palade小体,用间接免疫荧光法检测CD31、CD34及CD44的表达。结果加VEGF的MVECs原代3d铺满瓶底,3～4d传一代;不加VEGF的MVECs原代7～12d铺满瓶底,7～8d传一代。鉴定时两种培养的MVECs表达是一致的。倒置显微镜观察细胞铺满瓶底时呈典型的铺路卵石样结构,免疫组化法第Ⅷ因子相关抗原阳性,透射电镜观察到细胞浆中的Weibel-Palade小体,间接免疫荧光法检测CD31、CD34表达阳性,CD44阴性。结论VEGF对MVECs体外培养的影响无显著意义。     

血管内皮生长因子在子宫疾病中的研究进展

血管内皮生长因子(VEGF)又称血管通透性因子(VPF),是具有高度特异性的促血管内皮细胞生长因子,能与肝素结合的双价糖蛋白分子,其蛋白质结构具有高度的保守性。血管内皮生长因子(VEGF)在子宫内膜的表达,反映了新生血管的形成,与疾病的发生发展密切相关。因此,研究VEGF在子宫内膜中的表达,可能为寻找子宫疾病的发生     

血管内皮生长因子与自然流产相关性研究

血管内皮生长因子(VEGF)是一种分泌糖基化多肽因子,具有强烈促血管生长及增加微血管通透性的作用,是一种特异性有丝分裂原,是人体生理性新生血管网形成的重要因子.血管发生和血管化是胎盘建立丰富的毛细血管网络以及胚胎发育的基础.研究发现[1]在正常妊娠的情况下,胎儿脐血VEGF有丰富的表达,说明VEGF在调控胎盘、脱膜血管网络发育中发挥着重要作用.本文就VEGF与自然流产相关性综述如下:     

VEGF诱导牛主动脉内皮细胞通透性升高及丹酚酸B对其的抑制作用(英文)

目的:考察血管内皮生长因子/血管通透因子(VEGF)对体外培养牛主动脉内皮细胞脂蛋白通透性的影响及丹酚酸B的抑制作用。方法:将不同浓度的VEG、丹酚酸B及培养基加入牛主动脉内皮细胞单层,与~(125)I-LDL共孵育,在不同的时间段用SN-695型液闪计数器测其通过细胞单层的百分率。结果:VEGF可显著增强牛主动脉内皮细胞单层对~(125)I-LDL的通透性(P<0.01),这种增加具有时间和剂量依赖性。丹酚酸B能显著抑制VEGF诱导的这种高通透(P<0.01)。结论:上述结果提示VEGF在动脉粥样硬化的形成和发展过程中起一定作用。丹酚酸B对VEGF诱导血管内皮通透性升高有显著的抑制作用。     

Inhibitory effect of extracts of Ginkgo biloba leaves on VEGF-induced hyperpermeability of bovine coronary endothelial cells in vitro

AIM: To study whether extract of Ginkgo biloba (EGb) can protect against atherosclerosis. METHODS: Confluent monolayers of bovine coronary endothelial cells (BCECs), bovine coronary smooth muscle cells (BCSMCs), and cocultures of the two were incubated with medium containing VEGF and/or EGb, and flux of 125I-labeled oxidized low density lipoprotein (ox-LDL) across the monolayers was measured. RESULTS: Incubation with VEGF significantly increased the permeability of BCEC monolayers to 125I-ox-LDL in a time- and concentration-dependent manner, but had no effect on permeability of BCSMCs or endothelial cells-smooth muscle cells cocultures. EGb significantly inhibited the VEGF-induced hyperpermeability of BCECs. CONCLUSION: VEGF was important in the formation and development of atherosclerosis. The inhibition of VEGF-induced permeability by EGb suggests that extracts of Ginkgo biloba leaves may have important clinical applications in the treatment of cardiovascular diseases.     

Oxidized low-density lipoprotein inhibits vascular endothelial growth factor-induced endothelial progenitor cell differentiation

1. Bone marrow-derived endothelial progenitor cells (EPC) in the peripheral blood of adult animals and humans have been shown to be incorporated into neovascularization. In contrast, hypercholesterolaemia impairs angiogenesis and collateral vessel formation in response to regional tissue ischaemia. We investigated whether oxidized LDL (oxLDL) affected human EPC differentiation. 2. When isolated human mononuclear cells (MNC) were incubated with vascular endothelial growth factor (VEGF), the number of differentiated, adherent EPC, as assessed by an in vitro culture assay, was increased in a dose-dependent manner (P < 0.01). When MNC were incubated with oxLDL at 1, 5 and 10 microg/mL in the presence of 100 ng/mL VEGF for 24 h, oxLDL dose-dependently reduced the number of differentiated, adherent EPC. 3. Vascular endothelial growth factor-induced EPC differentiation was significantly inhibited by pharmacological phosphatidylinositol 3-kinase blockers (either 10 nmol/L wortmannin or 10 micromol/L LY294002). Interestingly, immunoblotting analysis revealed that oxLDL dose-dependently led to dephosphorylation and, thus, deactivation of Akt in the presence of VEGF. Finally, these inhibitory effects induced by oxLDL were abolished by pretreatment with 1 micromol/L atorvastatin (P < 0.01). 4. Our data indicate that oxLDL inhibits VEGF-induced EPC differentiation through the dephosphorylation of Akt.     

Role of nitric oxide, prostaglandins and tyrosine kinase in vascular endothelial growth factor-induced increase in vascular permeability in mouse skin

We investigated role of nitric oxide (NO), prostaglandins (PG) and tyrosine kinase in vascular endothelial growth factor (VEGF)-induced increase in vascular permeability in mouse skin. Subcutaneous injection of VEGF (0.5–2.0 ng/site) induced dose- and time-dependent increase in vascular permeability at the injection site determined by a leakage of Pontamine sky blue. VEGF (1 ng/site)-induced dye leakage was partially inhibited by N^G-nitro-l-arginine methyl ester (an inhibitor for both constitutive and inducible NO synthase) (5 and 10 mg/kg, i.v.) and by aminoguanidine (a selective inducible NO synthase inhibitor) (5–20 mg/kg, i.v.), but not by an inactive enantiomer, N^G-nitro-d-arginine methyl ester (10 mg/kg, i.v.). Pretreatment with an intraperitoneal injection of indomethacin (a nonselective cyclooxygenase inhibitor) (5 mg/kg) or N-(2-cyclohexyloxy-4-nitrophenyl) methanesulphonamide (a cyclooxygenase-2 selective inhibitor) (1–100 μg/kg) almost completely inhibited the effect of VEGF (1 ng/site). Coadministration of PGE₂ (3 and 30 nmol/site) with VEGF did not restore the inhibitory effect of indomethacin on VEGF (1 ng/site)-induced increase in vascular permeability. Lavendustin A (a selective tyrosine kinase inhibitor) (10 and 50 μg/kg, s.c.) dose-relatedly inhibited the VEGF (1 ng/site)-induced increase in dye leakage, whereas its negative control, lavendustin B (10 μg/kg, s.c.) had no effect. Another tyrosine kinase inhibitor, genistein (2.5 mg/kg, s.c.) also inhibited the response. Cycloheximide (a protein biosynthesis inhibitor) (35 mg/kg, s.c.) suppressed the response of VEGF (1 ng/site). Histologically, no cellular infiltration was observed in the area of VEGF injection. These results suggest that increased vascular permeability induced by VEGF is mediated by local production of NO and arachidonic acid metabolites other than PGE₂, which are most probably produced by inducible NO synthase and cyclooxygenase-2, respectively. Protein tyrosine kinase-mediated phosphorylation and synthesis of any new proteins are likely to be required in this effect of VEGF in mouse skin. Received: 18 November 1996 / Accepted: 30 May 1997     

慢性低O2高CO2大鼠血管内皮生长因子表达及参一胶囊的影响

目的 :探讨血管内皮生长因子 (VEGF)在低氧性肺动脉高压形成中的意义及参一胶囊对其影响。方法 :采用ELISA法、透射电镜、原位杂交技术等方法 ,观察正常对照组、低O2 高CO2 4周组、低O2 高CO2 4周 参一胶囊组大鼠肺动脉平均压 (mPAP)、右心室重量比 (RV LV S)、血清和肺组织的VEGF的含量、肺细小动脉的超微结构、肺组织VEGFmR NA表达的变化。结果 :低O2 高CO2 组大鼠的mPAP、RV LV S、血清和肺组织的VEGF的含量明显高于正常对照组 (P <0 .0 1)。低O2 高CO2 4周 参一胶囊组大鼠mPAP、RV LV S、血清VEGF显著低于低O2高CO2 组 (P <0 .0 1) ,肺组织的VEGF的含量也低于低O2 高CO2 组 (P <0 .0 5 )。低O2 高CO2 组大鼠肺细小动脉中膜平滑肌细胞明显增生、胶原纤维较正常对照组增多 ,低O2 高CO2 4周 参一胶囊组较低O2 高CO2 组则明显减轻。原位杂交显示低O2 高CO2 组大鼠肺细小动脉VEGFmRNA较正常对照组明显增加 (P <0 .0 1) ,而低O2 高CO2 4周 参一胶囊组与低O2 高CO2 组比较 ,则明显降低(P <0 .0 5 )。结论 :VEGF参与了慢性低氧性肺动脉高压的形成 ,参一胶囊可通过抑制VEGF的作用而有效地降低肺动脉高压     

2型糖尿病对脑梗死患者血小板衍生内皮细胞生长因子和血管内皮细胞生长因子的影响

目的观察2型糖尿病对急性脑梗死患者血清血小板衍生内皮细胞生长因子(PD-ECGF)和血管内皮细胞生长因子(VEGF)的影响。方法入选急性脑梗死患者73例(其中非伴随糖尿病患者32例设为A组,伴随糖尿病患者41例设为B组)、同期住院的合并2型糖尿病的非脑血管病患者30例(C组),以及不伴糖尿病的非脑血管病患者30例(D组)为研究对象。用双抗体夹心酶联免疫吸附实验法检测A组和B组患者在发病后第1,3,7,10~14天时的血清PD-ECGF、VEGF浓度,C组和D组患者检测入院第1天的血清PD-ECGF、VEGF浓度。用美国国立卫生院神经功能缺损评分(NIHSS)量表对A组和B组进行NIHSS评分。结果发病后1,3,7,10~14 d,A组的PD-ECGF分别为(5.93±1.25),(5.93±1.25),(4.19±1.23)和(3.67±1.06)μg·m L^-1,B组的PD-ECGF分别为(2.88±0.54),(2.84±0.53),(2.81±0.41)和(2.86±0.49)μg·m L^-1;A组的VEGF分别为(172.32±31.91),(254.36±49.56),(321.80±52.20)和(195.91±40.25)pg·m L^-1,B组的VEGF分别为(154.91±31.84),(158.69±29.27),(156.92±38.16)和(159.64±27.21)pg·m L^-1,2组各个时间点比较,差异均有统计学意义(均P<0.05)。入院第1天,C组和D组的PD-ECGF分别为(2.25±0.49)和(2.79±0.51)μg·m L^-1,VEGF分别为(94.90±19.85)和(151.11±30.33)pg·m L^-1,差异均有统计学意义(均P<0.05)。发病后第1天,A组和B组的NIHSS评分分别为(12.52±3.25)和(12.89±2.56)分,差异无统计学意义(P>0.05);发病后第10~14天,A组和B组的NIHSS评分分别为(4.24±1.87)和(6.48±2.15)分,差异有统计学意义(P<0.05)。结论 2型糖尿病可通过降低脑梗死患者血清PD-ECGF和VEGF表达水平,影响患者的预后。     

苏拉明对慢性低氧高二氧化碳大鼠血管内皮生长因子的影响

目的　探讨血管内皮生长因子 (VEGF)在低氧性肺动脉高压形成中的意义及苏拉明对其的影响。方法　将 30只SD大鼠分成正常对照组 (N组 )、低O2 高CO2 4wk组 (F组 )、低O2 高CO2 4wk +苏拉明组 (S组 ) ,采用ELISA法、透射电镜、免疫组化和原位杂交技术等方法 ,观察各组大鼠肺动脉平均压 (mPAP)、右心室重量比 (RV/LV +S)、血清和肺组织VEGF含量、肺细小动脉超微结构、肺组织VEGF及其基因表达的变化。结果　①F组大鼠mPAP、RV/LV +S、血清和肺组织VEGF的含量高于N组 (P <0 0 1) ,S组大鼠mPAP、RV/LV +S、血清VEGF低于F组 ,(P <0 0 1) ,而肺组织VEGF的含量也低于F组 ,(P <0 0 5 )。②F组中膜平滑肌细胞明显增生、胶原纤维较N组增多 ,S组较F组则减轻。③免疫组化、原位杂交显示F组大鼠肺细小动脉VEGF及其mRNA与N组比较增加 (P <0 0 1) ,而S组与F组比较 ,则降低 (P <0 0 5 ,P <0 0 1)。结论　VEGF参与了慢性低氧性肺动脉高压的形成 ,苏拉明通过抑制VEGF的作用而有效地降低低氧所致的肺动脉高压。     

Dauricine inhibits insulin-like growth factor-Ⅰ-induced hypoxia inducible factor la protein accumulation and vascular endothelial growth factor expression in human breast cancer cells

Aim： To investigate the effects of dauricine （Dau） on insulin-like growth factor-Ⅰ （IGF-Ⅰ）-induced hypoxia inducible factor 1α （HIF-1α） and vascular endothelial growth factor （VEGF） expression in human breast cancer cells （MCF-7）. Methods： Serum-starved MCF-7 cells were pretreated for 1 h with different concentrations of Dau, followed by incubation with IGF-Ⅰ for 6 h. HIF-1α and VEGF protein expression levels were analyzed by Western blotting and ELISA, respectively. HIF-1α and VEGF mRNA levels were determined by real-time PCR. In vitro angiogenesis was observed via the human umbilical vein endothelial cell （HUVEC） tube formation assay. An in vitro invasion assay on HUVECs was performed. Results： Dau significantly inhibited IGF-Ⅰ-induced HIF-1α protein expression but had no effect on HIF-1α mRNA expression. However, Dau remarkably suppressed VEGF expression at both protein and mRNA levels in response to IGF-Ⅰ. Mechanistically, Dau suppressed IGF-Ⅰ-induced HIF-1α and VEGF protein expression mainly by blocking the activation of PI-3K/AKT/mTOR signaling pathway. In addition, Dau reduced IGF-Ⅰ-induced HIF-1α protein accumulation by inhibiting its synthesis as well as by promoting its degradation. Functionally, Dau inhibited angiogenesis in vitro. Moreover, Dau had a direct effect on IGF-Ⅰ-induced invasion of HUVECs. Conclusion： Dau inhibits human breast cancer angiogenesis expression, which may provide a novel potential mechanism for by suppressing HIF-1α protein accumulation and VEGF the anticancer activities of Dau in human breast cancer.