阿托伐他汀对血管新生的促进作用

目的探讨阿托伐他汀对血管新生的促进作用及其作用机制。方法建立野生型C3H／He小鼠下肢缺血模型,观察用药后肢体血流、毛细血管数、血管内皮生长因子（VEGF）蛋白表达。并行离体实验（血管新生共同培养）,计数血管样结构物管腔形成数。结果阿托伐他汀使实验小鼠术后缺血肢血流明显改善,缺血肢与非缺血肢血流面积比明显增加;缺血肢毛细血管密度明显增加,VEGF蛋白表达增强。血管新生共同培养,血管样结构物管腔数明显高于对照组和加入血管新生抑制剂组,但与阳性对照组比较无明显差异。结论阿托伐他汀有促进血管新生的作用。     

The effects of cadmium on VEGF-mediated angiogenesis in HUVECs

Cadmium (Cd) is a highly toxic element that causes morphologic alterations and dysfunction in blood vessels. The altered vascular function caused by cadmium has been implicated in a range of chronic diseases, including hypertension. The effects of cadmium are a multisystem phenomenon involving inflammation, hypertrophy, apoptosis, angiogenesis and important processes involved in vascular remodeling systems. Vascular endothelial growth factor (VEGF) plays a major role in cell growth and angiogenesis under pathologic conditions. VEGF secretion is related to anti-apoptosis protein expression and attenuates apoptosis in endothelial cells. This study examined the VEGF-dependent mechanisms of angiogenesis and apoptosis in cadmium-treated endothelial cells (HUVECs). The effects and mechanisms of cadmium in endothelial cells (HUVECs) were examined by exposing the cells to different doses of cadmium chloride (2.5-40 μ m). After the cadmium treatment, the angiogenesis and apoptosis mechanisms related to VEGF in cadmium-treated HUVECs were examined. As a result, the low concentration of cadmium increased the tube formation in HUVECs. In addition, cadmium at concentrations of 5 and 10 μ m increased VEGF secretion and VEGFR2 activity, which suggest that cadmium affects the growth of blood vessels. All three MAPK pathways, namely ERK, JNK and p38, were activated by cadmium in HUVECs. However, high concentrations of cadmium caused cell damage, disrupted tube formation and inhibited VEGF expression and the activities of VEGFR2 and MAPK in HUVECs. Cadmium has dual functions through VEGF-dependent mechanisms in a dose-dependent manner. In this study, the dual effects of cadmium might alter angiogenesis and induce apoptosis through VEGF pathways in HUVECs.     

Hypericin in the dark inhibits key steps of angiogenesis in vitro

Photoactivated hypericin has a potent cytotoxic effect over a wide range of cells. However, very recently hypericin has been shown to have antitumoral and antimetastatic effects in the dark. The aim of this study was to test whether hypericin in the dark affects angiogenesis. Different in vitro assays were used to study the potential effects of this compound on key steps of angiogenesis, namely, a colorimetric assay of cell proliferation/viability, a tubular formation on Matrigel assay, zymographic assays for gelatinases and urokinase, a wound assay for migration and a fluorometric assay for invasion through Matrigel. In this report, we show for the first time that hypericin kept in the dark inhibits several key steps of the angiogenic process, namely, bovine endothelial cell proliferation, formation of tubular-like structures on Matrigel, migration and invasion, as well as extracellular matrix degrading urokinase.     

急性白血病患者骨髓组织血管新生与Bcl-2蛋白关系的研究

目的分析急性白血病患者骨髓病理切片中VEGF及Bcl-2蛋白的表达和微血管生成之间的相关性,并研究急性白血病患者骨髓组织血管新生与Bcl-2蛋白的关系。方法用免疫组织化学染色方法(EnVison)检测35例急性白血病患者和35例对照组骨髓病理切片中的VEGF,Bcl-2表达情况,并用第八因子相关抗原(FactorⅧ-related Antigen,FVIⅡ)标记血管内皮细胞,将免疫组化染色结果转化为平均光密度值进行定量分析。结果急性白血病患者Bcl-2蛋白阳性表达、MVD、VEGF含量均明显高于对照组,与对照组比较有显著性差异(P<0.01)。通过对这3者进行两两相关性分析,结果MVD与VEGF表达呈正相关;Bcl-2蛋白阳性率与VEGF表达呈正相关;Bcl-2蛋白阳性率与MVD表达呈正相关。结论由于VEGF的表达,诱导产生更多的Bcl-2蛋白来降低急性白血病细胞凋亡,从而增加急性白血病的恶性程度,再加上本身促血管生成的作用,血管生成随之增加,从而增加了急性白血病的治疗难度。     

Inhibition of angiogenesis by propolis

Propolis, obtained from honeybee hives, has been used in Oriental folk medicine as an anti-inflammatory, anti-carcinogenic, and immunomodulatory agent. There is considerable evidence suggesting that angiogenesis and chronic inflammation are codependent. Blockage of angiogenesis results in an anti-inflammatory effect. Ethanol (EEP) and ether extracts of propolis (REP), and caffeic acid phenethyl ester (CAPE), an active component of propolis, were examined for their anti-angiogenic activities using the chick embryo chorioallantoic membrane (CAM), and the calf pulmonary arterial endothelial (CPAE) cell proliferation, assays. The presence of EEP, REP and CAPE inhibited angiogenesis in the CAM assay and the proliferation of CPAE cells. The results suggest that anti-angiogenic activities of EEP, REP and CAPE are also responsible for their anti-inflammatory effect.     

外泌体在肥胖症中的研究进展

外泌体是细胞分泌的一种囊泡样小体,可通过受体与配体间的相互作用刺激靶细胞,或通过向靶细胞转移各种生物活性分子如膜受体、蛋白质、mRNA和miRNA等方式在细胞间通讯中扮演重要角色,其中研究最多的是miRNAs。最近研究表明,外泌体中特定的miRNAs通过调控脂肪的形成、经典棕色脂肪组织功能和白色脂肪组织褐变过程,以及参与脂肪组织巨噬细胞的活化状态,在肥胖症的病理过程中发挥关键作用。     

高迁移率族蛋白A2在肿瘤发生和血管形成中的双重作用

目的:探讨高迁移率族蛋白A2(HMGA2)在肿瘤发生和血管形成中的作用。方法:采用Clontech公司软件设计靶向人HMGA2基因的5条小干扰RNA(siRNA)序列,常规培养肿瘤细胞系和血管内皮细胞系,利用脂质体2000将HM-GA2 siRNA导入细胞,通过MTT方法和Tran-swell模型检测细胞的增殖和迁移能力,采用小管形成实验检测血管内皮细胞的小管形成能力,荧光定量PCR方法检测细胞内的HMGA2 mRNA的变化。结果:5条siRNA中,HMGA2 siR-NA1、3、5不但能抑制肿瘤细胞的增殖,还可抑制血管内皮细胞的增殖、迁移和小管形成,尤其以HMGA2 siRNA5最为明显,处理组细胞的相对增长率分别为:Hela 63.2%±6.5%(P<0.01);人肺腺癌SPC-A1,86.8%±3.5%(P<0.01);人脐静脉内皮细胞(ECV-304),58.5%±6.3%(P<0.01);人膀胱上皮细胞株(HUVEC),60.3%±7.3%(P<0.01)。HMGA2 siRNA5抑制两种血管内皮细胞的迁移(P<0.01),并降低HM-GA2基因的表达(P<0.01)。结论:HMGA2除了在肿瘤发生过程中起作用之外,在血管形成中同样具有重要作用。     

Arsenite suppresses angiogenesis of vascular endothelial cells mediated by Platelet Derived Growth Factor Receptor-beta

The present study aimed to investigate the effects of sodium arsenite (NaAsO₂) on the angiogenesis of human umbilical vein endothelial cells (HUVECs) and the mechanism involved. Firstly, a Matrigel-based in vitro angiogenesis assay demonstrated that arsenite suppressed the angiogenesis of HUVECs in a dose-dependent manner. Then by using a global inhibitor for multiple growth factor receptors (E7080) and a specific inhibitor of PDGFR-beta (CP-673451), we found that E7080 completely prevented and CP-673451 significantly decreased the angiogenesis of HUVECs. This suggested that angiogenesis of HUVECs depends on the signal pathway mediated by tyrosine kinase receptors and that among them, PDGFR-beta has an important regulatory function. Finally by using porcine aortic endothelial cells which stably express human PDGFR-beta, we found that arsenite suppressed the angiogenesis mediated by PDGFR-beta. Based on these results, we conclude that arsenite suppressed the angiogenesis of the vascular endothelial cells, that this effect is mediated by PDGFR-beta, and postulate that it might contribute to the injuries of blood vessel in arsenism.     

Pseudolarix acid B inhibits angiogenesis by antagonizing the vascular endothelial growth factor-mediated anti-apoptotic effect

Angiogenesis is controlled by a number of growth factors, including vascular endothelial growth factor (VEGF). In this study, pseudolarix acid B, isolated from the traditional Chinese medicinal plant Pseudolarix kaempferi and originally identified as an early pregnancy-terminating agent, was evaluated for its potential as an angiogenesis inhibitor, using in vitro and in vivo models. After exposure to pseudolarix acid B 0.625-5 microM for 72 h, the proliferation of human umbilical vein endothelial cells was significantly inhibited. Pseudolarix acid B 0.313-2.5 microM for 24 h potently blocked the VEGF-induced tube formation of human umbilical vein endothelial cells in a dose-dependent manner. Matrigel plug assays disclosed that pseudolarix acid B reduced angiogenesis induced by VEGF in vivo. In addition, pseudolarix acid B antagonized VEGF-mediated anti-apoptotic effects on serum-deprived human umbilical vein endothelial cells and increased apoptosis of endothelial cells induced by VEGF in Matrigel plug assays. Moreover, pseudolarix acid B significantly inhibited VEGF-induced tyrosine phosphorylation of kinase insert domain-containing receptor/fetal liver kinase-1 (KDR/flk-1), in correlation with a marked decrease in the phosphorylation of Akt and extracellular signal-regulated kinases (ERK). These findings collectively suggest that pseudolarix acid B possesses anti-angiogenic activity. One of the main anti-angiogenesis mechanisms of pseudolarix acid B may involve antagonism of the VEGF-mediated anti-apoptosis effect via inhibition of KDR/flk-1, ERK1/2, and Akt phosphorylation in endothelial cells.     

Radioiodination,purification, and evaluation of antihuman tumor-derived immunoglobulin G light chain monoclonal antibody in tumor-bearing nude mice

We report the synthesis and biological evaluation of ¹³¹I-labeled antihuman tumor-derived immunoglobulin G (IgG) light chain monoclonal antibody (4E9) ([¹³¹I]I-4E9) as a promising probe for tumor imaging. [¹³¹I]I-4E9 was synthesized in radiochemical yield of 89.9 ± 4.7% with radiochemical purity of more than 99%. [¹³¹I]I-4E9 showed high stability in normal saline and human serum. In cell uptake studies, [¹³¹I]I-4E9 exhibited favorable binding affinity and high specificity in HeLa MR cells. In biodistribution studies, [¹³¹I]I-4E9 showed high tumor uptake, high tumor/non-tumor ratios, and specific binding in BALB/c nu/nu mice bearing human HeLa MR xenografts. Single-photon emission computerized tomography (SPECT) imaging of [¹³¹I]I-4E9 in the HeLa MR xenograft model demonstrated clear visualization of tumor after 48 h and confirmed specific binding in tumor. These findings suggest that [¹³¹I]I-4E9 possesses favorable biological characteristics and warrants further investigation as a prospective probe for imaging and treatment of cancers.     

Role of miR-199b-5p in regulating angiogenesis in mouse myocardial microvascular endothelial cells through HSF1/VEGF pathway

Our study explored effects of miR-199b-5p on angiogenesis in mouse myocardial microvascular endothelial cells (MMVECs) and the involved working mechanisms. We applied explant culture to incubate C57/BL6 mouse MMVECs. Lipofection was used to transfect miR-199b-5p mimic, miR-199b-5p inhibitor and miR-199b-5p scramble respectively. MMVECs were divided into miR-199b-5p up-regulation, miR-199b-5p down-regulation and control groups based on above sequence. Expressions of miR-199b-5p, heat shock factor protein 1 (HSF1) mRNA were assessed by real-time quantitative polymerase chain reaction (RT-QPCR). Expressions of HSF1 and vascular endothelial growth factor (VEGF) were assessed by Western Blotting. Cell proliferation was assessed by CCK8. Tubule formation assay was conducted to assess formation of blood vessels. Results showed that miR-199b-5p up/down-regulation groups exhibited no obvious differences in the expressions of HSF1 mRNA compared to control group. However, miR-199b-5p up-regulation group recorded lower expressions of HSF1 and VEGF in the level of protein, and reduced cell proliferation and tubule formation. Whereas, miR-199b-5p down-regulation group presented the contrary results. The experiment indicated that miR-199b-5p can regulate proliferation and angiogenesis in mouse MMVECs through the pathway of HSF1/VEGF.     

骨相关细胞来源外泌体miRNA调节骨形成的研究进展

外泌体是一种由细胞分泌的具有脂质双分子层结构的杯状细胞外囊泡,直径约30-150 nm。近年来,研究表明骨组织中的各类骨细胞产生的外泌体不仅可介导生理情况下骨髓微环境内的细胞间通讯,维持骨髓微环境的稳态,还参与骨骼疾病的发病过程。该文将着重探讨骨相关细胞来源的外泌体miRNA对骨形成的调节作用。     

魟鱼软骨多糖对人脐静脉内皮细胞形成新生血管的影响

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.     

Insulin-like growth factor binding protein-7 (IGFBP7) blocks vascular endothelial cell growth factor (VEGF)-induced angiogenesis in human vascular endothelial cells

Insulin-like growth factor binding protein-7 (IGFBP7) and vascular endothelial growth factor (VEGF) are expressed in vascular endothelial cells in several tumor types. In this study, we examined the effect of IGFBP7 on VEGF-induced tube formation in cultured human umbilical vein endothelial cells (HUVECs) and its potential action in the modulation of VEGF signaling in vascular cells. IGFBP7 treatment suppressed VEGF-induced tube formation, proliferation, and the phosphorylation of mitogen-activated protein kinase kinase (MEK) and extracellular signal-regulated kinase (ERK) 1/2 in HUVECs. IGFBP7 attenuated VEGF-enhanced cyclooxygenase (COX)-2 and VEGF mRNA expression, and prostaglandin E₂ secretion. Knocking down endogenous IGFBP7 enhanced COX-2 and VEGF mRNA expression. A significant increase in IGFBP7-induced caspases was not observed in the presence of VEGF. These findings indicate that IGFBP7 can modulate the stimulatory effect of VEGF on angiogenesis by interfering with VEGF expression as well as VEGF signaling and not by inducing apoptosis.     

脂肪干细胞来源外泌体携带miR-27抑制白色脂肪的棕色化

目的 探讨脂肪干细胞（ASC）来源的外泌体在白色脂肪棕色化中的作用。方法 分离培养并鉴定小鼠ASC细胞;慢病毒转染构建过表达 miR-27的 ASC细胞;超高速离心提取正常及过表达 miR-27的 ASC细胞分泌的外泌体,实时荧光定量核酸扩增（qRT-PCR）分析外泌体中 miR-27的表达量;高脂喂食构建肥胖小鼠模型,分别注射过表达 miR-27外泌体（过表达组）、正常 ASC外泌体（正常表达组）及生理盐水（对照组）,在寒冷暴露条件下监测体质量变化;剥离小鼠附睾皮下脂肪组织和肩胛骨脂肪组织,比较组织大小,蛋白免疫印迹法（Western blot）检测解偶联蛋白 1（UCP1）、过氧化物酶体增殖剂激活受体 γ（PPARγ）、含 PR结构域的锌指蛋白 16（PRDM16）、过氧化物酶体增殖子激活受体 γ共激活因子 1α（PGC-1α）的表达。结果 成功提取 ASC及其外泌体,并成功转染 miR-27;ASC及其外泌体中的 miR-27显著高于白色脂肪组织（P＜0.05）。与对照组相比,过表达组及正常表达组的小鼠体质量下降幅度小,随时间的增加效果更加明显（P＜0.05）。过表达组及正常表达组的小鼠的附睾皮下脂肪组织较对照组的小鼠要稍大;而肩胛骨脂肪组织的大小无明显变化。正常表达组与过表达组的 UCP1、PPARγ、PRDM16及 PGC-1α的表达水平较对照组下降（P＜0.05）。结论 脂肪干细胞来源外泌体能够抑制白色脂肪细胞的棕色化。     

间充质干细胞来源的外泌体抑制乳腺癌细胞生长的研究

摘要： 目的 研究脐带间充质干细胞来源的外泌体 （MSCs-Exo） 对乳腺癌细胞生长的影响。方法 利用生物发光成像技术的双报告基因 （萤火虫荧光素酶-绿色荧光蛋白, Fluc-GFP） 载体, 通过慢病毒转染构建人乳腺癌MDA- MB-231细胞系 （231-Fluc-GFP）, 以便在体内可以对细胞进行实时监测。分别采用MSCs-Exo （MSCs-Exo组） 和PBS （对照组） 处理细胞, 体外实验对2组细胞进行形态学观察、 增殖、 存活、 STAT3及其下游基因表达的检测; 通过皮下注射2组细胞建立裸鼠体内乳腺癌模型, 对不同处理条件下的细胞成瘤情况进行分析。结果 体外实验结果显示 MSCs-Exo处理后乳腺癌MDA-MB-231细胞增殖受到了抑制, 在处理第3天时2组细胞数差异有统计学意义 （P＜ 0.05）; 处理后细胞存活率降低 （P＜0.01）; 外泌体处理组STAT3及其下游基因C-MYC, BCL-XL, NANOG, OCT4, SOX2 表达下降。体内实验结果显示MSCs-Exo处理组肿瘤细胞在体内的生长受到抑制。结论 脐带间充质干细胞来源的外泌体抑制乳腺癌细胞的生长。     

注射用丹参多酚酸对氧糖剥夺/复氧复糖小鼠脑微血管内皮细胞血管生成的影响及机制研究

目的 研究注射用丹参多酚酸（SAFI）对氧糖剥夺/复氧复糖（OGD/R）损伤后小鼠脑微血管内皮细胞（BEND3）增殖、迁移、成管能力的影响及机制。方法 CCK-8法检测SAFI对正常BEND3细胞活力的影响,筛选出安全作用浓度。取正常生长的对数期BEND3细胞,分为对照组、模型组、SAFI（0.63、1.25、2.50、5.00、10.00 μg·mL^-1）组,模型组与SAFI组建立OGD/R模型,缺氧缺糖4 h、复氧复糖24 h;CCK-8法检测BEND3细胞活力;划痕实验检测BEND3细胞迁移能力;基质胶成管实验检测BEND3细胞成管能力;Western blotting法检测BEND3细胞血管内皮生长因子A（VEGFA）、血管生成素-1 （Ang-1）、Ang-2蛋白表达。结果 与对照组比较,模型组细胞活力、细胞迁移率及细胞成管血管网络的交叉点数、节点数、分支点数、血管总长度均显著降低（P＜0.05、0.01）;与模型组比较,SAFI浓度为2.50、5.00、10.00 μg·mL^-1时细胞活力、细胞迁移率及细胞成管血管网络的交叉点数、节点数、分支点数、血管总长度、网眼总面积和VEGFA和Ang-1、Ang-2蛋白表达量均显著上升（P＜0.05、0.01）,且作用呈浓度相关性。结论 SAFI可提高BEND3细胞OGD/R损伤后的增殖能力、迁移能力、成管能力,机制可能与上调VEGFA和Ang-1、Ang-2蛋白表达相关。     

阿托伐他汀对缺氧致人脐静脉内皮细胞损伤的保护作用

目的观察阿托伐他汀对缺氧导致人脐静脉内皮细胞(HUVECs)损伤的保护作用。方法体外培养HUVECs,建立缺氧模型,采用MTT法测定细胞增殖,透射电子显微镜技术观察细胞的微观结构;检测细胞培养液中LDH、NO、ET-1、Ang-Ⅱ及6-keto-PGF1α水平。结果阿托伐他汀能够促进缺氧HUVECs的增殖,稳定细胞的微观结构,显著降低细胞内LDH的释放及ET-1的分泌(P<0.01),提高NO、PGI2的分泌(P<0.01)。结论阿托伐他汀对缺氧导致HUVECs损伤具有明显的保护作用。     

非可兴奋性内皮细胞α7受体与血管新生

烟碱受体α7亚型 (α7nicotinicacetylcholinereceptor,α7nAChR)广泛分布于中枢和外周神经系统 ,是中枢神经系统重要神经递质受体 ,参与神经通路形成、维持和多种生理功能调节。近年来研究发现内皮细胞、血管平滑肌细胞、肺上皮细胞、皮肤角质细胞等非神经元细胞表达α7受体 ,并参与细胞有丝分裂、分化、细胞骨架形成、细胞间联接、运动和迁移等细胞机制调节。体外、体内试验表明α7受体参与内皮细胞多种生物活性物质的分泌和释放 ,参与内皮细胞与其它细胞间信号转导 ,参与内皮细胞血管新生调节。尤其是内皮细胞α7受体与血管新生关系的研究 ,揭示了内皮细胞存在调节血管新生药物作用新靶标。