The effects of microRNA-34a regulating Notch-1/NF-κB signaling pathway on lipopolysaccharide-induced human umbilical vein endothelial cells

BACKGROUND: Notch-1/NF-κB signaling plays a key role in the cecal ligation and puncture(CLP)-induced sepsis. This study aims to investigate the intervention effects of microRNA-34a(miR-34a) lentivirus regulating Notch-1/NF-κB signaling pathway on lipopolysaccharide(LPS)-induced human umbilical vein endothelial cells(HUVEC).METHODS: HUVEC were divided into four groups as the following: they were infected with negative control lentivirus(NC group) or miR-34a lentivirus(OE group); LPS(1 g/mL) was added on the third day on the basis of NC group and OE group for 24 hours(NC+LPS group or OE+LPS group). The levels of TNF-α, IL-1β, IL-6, and IL-10 in the cell supernatants, and the mRNA and protein expression of Notch-1 and NF-κB in the HUVEC were evaluated.RESULTS: After 24 hours, the levels of TNF-α, IL-1β, IL-6 in the cell supernatants and the protein expression of NF-κB from NC+LPS group were significantly higher than those of NC group, but IL-10 level and the protein expression of Notch-1 in NC+LPS group were the opposite. After intervention of miR-34a lentivirus, the cell supernatants TNF-α and the protein expression of NF-κB in OE+LPS group after 24 hours markedly decreased compared to NC+LPS group. While the cell supernatants IL-1β and IL-6 and the mRNA expression of NF-κB slightly decreased in OE+LPS group, IL-10 and the mRNA and protein expression of Notch-1 were the opposite.CONCLUSION: miR-34a regulating Notch-1/NF-κB signaling pathway can reduce the HUVEC damage caused by LPS stimulation.

Martentoxin, a large-conductance Ca^(2+)-activated K^+ channel inhibitor, attenuated TNF-α-induced nitric oxide release by human umbilical vein endothelial cells

Martentoxin, a 4,046 Da polypeptide toxin purified from the venom of the scorpion Buthus martensii Karsch, has been demonstrated to block large-conductance Ca2＋-activated K＋ （BKca） channels; however, its biological roles are still largely unknown. In the present study, we investigated the pharmacological effects of martentoxin on regulating the production of nitric oxide induced by TNF-a in human umbilical vein endothelial cells （HU- VECs）. We found that, 1, 10 and 100 ~tmol/L martentoxin decreased nitric oxide production by HUVECs ex- posed to 10 ng/mL TNF for 6, 12 and 24 hours. We further demonstrated that martentoxin inhibited the activity of iNOS and retarded the down-regulation of eNOS mRNA induced by TNF-a. Therefore, martentoxin could be a potential therapeutic agent for vascular diseases.

Knockdown of Ezrin Suppresses the Migration and Angiogenesis of Human Umbilical Vein Endothelial Cells In Vitro

Progressive tumor growth is dependent on angiogenesis. The mechanisms by which endothelial cells（ECs） are incorporated to develop new blood vessels are not well understood. Recent studies reveal that the ezrin radixin moesin（ERM） family members are key regulators of cellular activities such as adhesion, morphogenetic change, and migration. We hypothesized that ezrin, one of the ERM family members, may play important roles in ECs organization during angiogenesis, and new vessels formation in preexisting tissues. To test this hypothesis, in this study, we investigated the effects of ezrin gene silencing on the migration and angiogenesis of human umbilical vein endothelial cells（HUVECs） in vitro. HUVECs were transfected with plasmids with ezrin-targeting short hairpin RNA by using the lipofectamine-2000 system. Wound assay in vitro and three-dimensional culture were used to detect the migration and angiogenesis capacity of HUVECs. The morphological changes of transfected cells were observed by confocal and phase contrast microscopy. Our results demonstrated that the decreased expression of ezrin in HUVECs significantly induced the morphogenetic changes and cytoskeletal reorganization of the transfected cells, and also reduced cell migration and angiogenesis capacity in vitro, suggesting that ezrin play an important role in the process of HUVECs migration and angiogenesis.

Kinase domain insert containing receptor promoter controlled suicide gene system selectively kills human umbilical vein endothelial cells

AIM: To study the selective killing of human umbilical vein endothelial cells (HUVECs) by a double suicide gene under the regulation of a kinase domain insert containing receptor (KDR) promoter and mediated by an adenoviral gene vector. METHODS: Human KDR promoter was cloned by polymerase chain reaction (PCR), and two recombinant adenoviral plasmids pAdKDR-CdglyTK, pAdCMV-CDglyTK were constructed according to a two-step transformation protocol. These two newly constructed plasmids were then transfected into 293 packaging cells to grow adenovirus, which were further multiplied and purifi ed. HUVECs and LoVo cells were infected with either of the two resultant recombinant adenoviruses (AdKDR-CDglyTK and AdCMV-CDglyTK) respectively, and the infection rates were estimated by detection of green ? uorescent protein (GFP) expression. Infected cells were cultured in culture media containing different concentrations of 5-? uorocytosine (5-FC) and ganciclovir (GCV), and the killing effects were measured. RESULTS: The two recombinant adenoviral plasmids pAdKDR-CdglyTK, pAdCMV-CDglyTK were successfullyconstructed and transfected into 293 cells. The resultant recombinant adenoviruses infected cells caused similar infection rates; and the infected cells exhibited different sensitivity to the prodrugs: HUVECs infected with AdCMV-CDglyTK and LoVo cells infected with AdCMV-CDglyTK were highly sensitive to the prodrugs, and HUVECs infected with AdKDR-CDglyTK were similarly sensitive but signifi cantly more sensitive than the LoVo cells infected with AdKDR-CdglyTK (P < 0.001). CONCLUSION: Selective killing of HUVECs may be achieved by gene transfer of double suicide gene under the regulation of the KDR promoter. This finding may provide an optional way to target gene therapy of malignant tumors by abrogation of tumor blood vessels. ? 2006 The WJG Press. All rights reserved.

Effect of IBD sera on expression of inducible and endothelial nitric oxide synthase in human umbilical vein endothelial cells

瞄准：在煽动性的肠疾病(IBD ) 学习内皮和可诱导的氮的氧化物 synthases (eNOS 和 i NOS ) 和他们的角色的表示。方法：我们检验了重量的单位的效果一在人的脐的静脉 endothelial (HUVEC ) 的功能和生存能力上与活跃 Crohn 的疾病(CD ) 和 ulcerative (UC ) 从病人获得了。HUVEC 面对与活跃 CD 或 UC 从病人包含健康控制，或浆液的分享的浆液的媒介为 0-48 h 是有教养的。eNOS 和 i NOS 的表示被免疫荧光设想，并且由西方的污点的测密度术确定了。增长活动被 Ki-67 免疫的计算机化的图象分析估计反应房间，并且也面对 NOS 禁止者测试了， 10 (-4) mol/L L 名字。Apoptosis 和坏死被 annexin-V-biotin 方法并且由分别地染色的 propidium 碘化物检验。结果：在 HUVEC 立即在到 UC 的暴露以后，浆液 eNOS 显著地被导致，在 12 h 到达一座山峰。相反，在 eNOS 的减少与 CD 重量的单位在孵化以后被观察一 eNOS 铺平的 and 在与控制(18%+/-16% 对 23%+/-15% P【0.01 ) 相比的 20 h 是最小的。UC 或 CD 浆液与控制相比在 i NOS 引起了重要增加(UC：300%+/-21% ；CD：275%+/-27% 对 108%+/-14% ， P【0.01 ) 。Apoptosis/necrosis 特征没在任何一个实验显著地不同。增加的增长活动与 L 名字面对 CD 浆液或术后疗法被检测。文化与 CD 浆液在 24 h 处理以后显示出像试管的形成。结论：IBD 重量的单位一在 eNOS/iNOS 的比率的唤起的变化，而没影响 HUVEC 的生存能力。这些同时包含了 eNOS 的下面规定和 i NOS 的起来规定，导致增加的增长活动并且可能 endothelial 的减少的反煽动性的保护。

Up-regulation interleukin-6 and interleukin-8 by activated protein C in lipopolysaccharide-treated human umbilical vein endothelial cells

Objective: To investigate the effect of activated protein C (APC) on inflammatory responses in human umbilical vein endothelial cells (HUVEC) stimulated with lipopolysaccharide (LPS). Methods: The second passage of collagenase digested HUVEC was divided into the following groups: serum free medium control group (SFM control), phosphate buffer solution control group (PBS control), LPS group with final concentration of 1 μg/ml (LPS group), APC group with final concentration of 7 μg/ml, Pre-APC group (APC pretreatment for 30 min prior to LPS challenge), and Post-APC group (APC administration 30 min after LPS challenge). Supernatant was harvested at 0, 4, 8, 12 and 24 h after LPS challenge. Interleukin-6 (IL-6) and Interleukin-8 (IL-8) levels were analyzed with ELISA. Cells were harvested at 24 h after LPS challenge, and total RNA was extracted. Mes-senger RNA levels for IL-6 and IL-8 were semi-quantitatively determined by RT-PCR. Results: Compared with control group, IL-6 and IL-8 levels steadily increased 4 to 24 h after LPS stimulation. APC treatment could increase LPS-induced IL-6 and IL-8 production. The mRNA levels of IL-6 and IL-8 exhibited a similar change. Conclusion: APC can further increase the level of IL-6 and IL-8 induced by LPS. The effect of these elevated cytokines is still under investigation.

Effects of Fumonisin B1 on Biomechanics and Cytoskeleton of Human Umbilical Vein Endothelial Cells

Objective Fumonisin B1(FB1)is an important mycotoxin in nature worldwide.The biomechanical properties of cells are closely related to their structure and function,and the cytoskeleton is the structural and functional basis of cells motility,and therefore,from a biomechanical point of view,the purpose of this study is to investigate the effects of FB1 on the biomechanical properties,migration capacity and cytoskeletal structure of human umbilical vein endothelial cells(HUVECs),which may lay an experimental foundation for further exploration of the toxicity mechanism of fumonisin.Methods HUVECs were cultured and treated with different concentrations of FB1.Then,CCK-8 kit was used to detect the effect of FB1 on the survival rate.The osmotic fragility of the cells was measured after treatment with different osmotic pressures for30 min.The cell membrane fluidity was measured by fluorescence polarization method.The cell electrophoretic mobility was measured by cell electrophoretic apparatus.The migration capacity of the cells was observed by scratch repair assay.The changes of reactive oxygen species and cytoskeletal structure were observed by confocal laser scanning microscopy.Finally,the mRNA and protein relative expression levels of cytoskeletal binding proteins were detected by real-time PCR,Western blotting and confocal laser scanning.Results The results of CCK-8 showed that FB1 could significantly inhibit the proliferation of HUVECs in a dose-and time-dependent manner.After treatment of HUVECs with FB1,the hypotonic resistance of the cell,cell surface charge,cell membrane fluidity and migration capacity were all weakened,while reactive oxygen species were significantly increased and the cytoskeletal structure was significantly reorganized.Furthermore,RTPCR results showed that the mRNA relative expression levels of cytoskeletal binding proteins,exception of actin,were down-regulated after treated with FB1.Besides,Western blotting and statistical analysis based on fluorescence intensity of laser confocal microscopy confirmed theses changes in protein level.Conclusions FB1 can significantly affect the biomechanical properties and motility of HUVECs,which may be directly correlated to the remodel of F-actin cytoskeleton,as well as the relative expression changes of cytoskeletal binding proteins.It is significant for further exploring the toxicity mechanism of fumonisin.

Comparison of conventional and directional freezing for the cryopreservation of human umbilical vein endothelial cells

AIM:To compare conventional slow equilibrium cooling and directional freezing(DF) by gauze package for cryopreservation of human umbilical vein endothelial cells(HUVECs).METHODS:HUVECs were randomly assigned to conventional freezing(CF) and DF by gauze package group. The two groups of HUVECs were incubated with a freezing liquid consisting of 10% dimethylsulfoxide(DMSO), 60% fetal bovine serum(FBS) and 30%Dulbecco’s modified Eagle’s medium(DMEM) and then put into cryopreserved tubes. CF group, slow equilibrium cooling was performed with the following program:precool in 4℃ for 30 min,-20℃ for 1h, and then immersion in-80℃ refrigerator. DF group, the tubes were packaged with gauze and then directional freezing in-80℃ refrigerator straightly. One month later, the vitality of HUVECs were calculated between two groups.RESULTS:There was no significant difference in the survival rate and growth curve between CF and DF groups. The DF group was significantly better than CFgroup in adherent rates, morphological changes and proliferative ability.CONCLUSION:In the conventional cryopreserved method, cells are slow equilibrium cooling by steps(4℃,-20℃ and finally-80℃), which is a complicated and time-consuming process. But the improved DF by gauze package method is better than conventional method, for which is convenient and easy to operate.

Changes in Human Umbilical Vein Endothelial Cells Induced by Endothelial Nitric Oxide Synthase Traffic Inducer

This study investigated the changes in human umbilical vein endothelial cells （HUVECs） induced by overexpression of endothelial nitric oxide synthase traffic inducer （NOSTRIN） and its role in cellular injury. Recombinant NOSTRIN-expressing and empty vectors were transfected into cultured HUVECs, and factor Ⅷ-related antigen was examined by using immunohistochemical analysis. Growth curves were generated for both transfected and untransfected cells and these indicated that the prolifera- tive ability of cells overexpressing NOSTRIN was significantly decreased. The expression of NOSTRIN and eNOS proteins was detected by using Western blot analysis, endothelial NOS （eNOS） activity was assayed by using spectrophotometry, and NO2-/NO3- levels were measured usin~ nitrate reductase. Immunohistochemical analysis demonstrated that all groups expressed NOSTRIN in the plasma mem- brane and cytoplasm, and Western blot analysis confirmed that NOSTR1N levels were significantly higher in cells transfected with the NOSTR1N plasmid （P〈0.01）. The activity of eNOS and the levels of NO2-/NO3 were significantly decreased in NOSTRIN overexpressing cells as compared with empty vector and untransfected cells （P〈0.01 and P〈0.01, respectively）. Morphological and ultrastructural changes were observed under light and electron microscopy, and it was found that NOS- TRIN-overexpressing cells were elongated with deformities of the karyotheca, injury to the plasma membrane, increased lipids in the cytoplasm, and shortened microvilli. This study showed that overex- pression of NOSTRIN had a significant effect on eNOS activity in HUVECs and resulted in significant cellular damage.

Effects of miR-21 antisense oligonucleotides on proliferation,migration and autophagy of human umbilical vein endothelial cells

Objective:To investigate the effects of microRNA-21 antisense nucleotide(AS-miR-21)on the proliferation,migration and autophagy of human umbilical vein endothelial cells(HUVECs).Methods:HUVECs were treated with1,000 nmol/L rapamycin for 6 h(rapamycin group)or ASmiR-21 transfection followed by 1,000 nmol/L rapamycin for6 h(AS-miR-21+rapamycin group).HUVECs without any treatment were defined as control group.The proliferation and migration abilities of HUVECs were detected by methyl thiazolyl tetrazolium(MTT)assay,scratch wound healing assay and transwell test,respectively.The expressions of microtubule-associated protein light chain 3 Ⅱ/Ⅰ(LC3 Ⅱ/Ⅰ)and Becline-1 were determined by western blotting.Results:The rapamycin group showed decreased OD value and migration rate,an increased ratio of LC3 Ⅱ/Ⅰ and up-regulated expression of Beclin-1 compared with the control group(P<0.05).The AS-miR-21+rapamycin group demonstrated lower OD value,migration rate,the number of migrated cells,and significantly higher ratio of LC3 Ⅱ/Ⅰ and Beclin-1 protein expression level than the control group and the rapamycin group(P<0.05).Conclusion:AS-miR-21 suppressed the autophagy,proliferation and migration in the HUVECs model of autophagy induced by rapamycin.

The Effects and Mechanism of GSA on Expression of MCP-1 in Cultured Human Umbilical Vein Endothelial Cells

Objectives To investigate the effects and mechanism of glycated serum albumin(GSA) on expression of Monocyte chemoattratant protein-1(MCP-1) in Endothelial Cells. Methods Human Umbilical Vein Endothelial Cells (HUVEC)are cultured with GSA of different concentrations and interfered by glycosylation products inhibitor Aminoguanidine (AG) and anti-oxidant N-acetylcy-steine (NAC), The expression of MCP-1 are evaluated by Immunocytochemistry and Sandwich ELISA. MDA content and SOD activity are determined by the technique of TBA and XOD respectively. Results GSA can stimulate MCP-1 production and secretion. Immunocytochemistry showed that after HUVECs were cultured with 50 mg/L GSA, expression of MCP-1 in group 4hrs, 8hrs and 12hrs was 1.3, 1.9 and 2.8 fold as much as that in control group (P < 0.01), and there was significant difference among the experiment groups(P < 0.01). Sandwich ELISA showed that expression of MCP-1 in three different groups was 1.6, 2.4 and 3.0 fold as much as that in control group(P < 0.01), and there was significant difference among the experiment groups(P < 0.01); GSA can cause the decrease of SOD activity(P < 0.05) and increase of MDA content(P < 0.01); AG and NAC can restrain obviously the expression of MCP-1 of HUVECs stimulated by GSA(P < 0.01); NAC can restrain the effect of GSA on SOD activity and MDA content in HUVECs (P < 0.05). Conclusions GSA can stimulate the expression of MCP-1 of endothelial cells by inducing endothelial cells oxidative stress.

Microbubble-enhanced ultrasound exposure improves gene transfer in vascular endothelial cells

AIM: To explore the effects of ultrasound exposure combined with microbubble contrast agent (SonoVue) on the permeability of the cellular membrane and on the expression of plasmid DNA encoding enhanced green fluorescent protein (pEGFP) transfer into human umbilical vein endothelial cells (HUVECs). METHODS: HUVECs with fluorescein isothiocyanate- dextran (FD500) and HUVECs with pEGFP were exposed to continuous wave (1.9 MHz, 80.0 mW/cm2) for 5 min, with or without a SonoVue. The percentage of FD500 taken by the HUVECs and the transient expression rate of pEGFP in the HUVECs were examined by fluorescence microscopy and flow cytometry, respectively. RESULTS: The percentage of FD500-positive HUVECs in the group of ultrasound exposure combined with SonoVue was significantly higher than that of the group of ultrasound exposure alone (24.0% ± 5.5% vs 66.6% ± 4.1%, P < 0.001). Compared with the group of ultrasound exposure alone, the transfection expression rate of pEGFP in HUVECs was markedly increased with the addition of SonoVue (16.1% ± 1.9% vs 1.5% ± 0.2%, P < 0.001). No statistical significant difference was observed in the HUVECs survival rates between the ultrasound group with and without the addition of SonoVue (94.1% ± 2.3% vs 91.1% ± 4.1%).CONCLUSION: The cell membrane permeability of HUVECs and the transfection efficiency of pEGFP into HUVECs exposed to ultrasound are significantly increased after addition of an ultrasound contrast agent withoutobvious damage to the survival of HUVECs. This non- invasive gene transfer method may be a useful tool for clinical gene therapy of hepatic tumors.

Expression of Soluble Vascular Endothelial Growth Factor Receptor-2 and Its Effect on Proliferation of Vascular Endothelial Cells

Vascular endothelial growth factors（VEGFs） respectively bind to each of three receptor tyrosine kinases（RTKs）,known as Flt-1,KDR and Flt-4.Since VEGFs and their respective families of receptor tyrosine kinases（VEGFRs） are critical proteins which can regulate vascular development during angiogenesis,we decided to explore the inhibitory effects of soluble kinase insert domain-containing receptor（sKDR） on endothelial cells and angiogenesis.Total RNA was extracted from human umbilical vein endothelial cells（HUVEC）,and cDNA of extracellular domains 1―4 was amplified and recombined with pQE40 vector.After being expressed,affinity purified,renatured and analyzed by Western blot,the sKDR was assayed for its effects on endothelial cells by [3-（4,5-dimethylthiazol-2-yl）2,5-diphenyltetrazolium bromide]（MTT）,and on angiogenesis by chick chorioallantoic membrane（CAM） experiment.sKDR cDNA of 1150 bp was obtained via real-time polymerase chain reaction（RT-PCR）,and sKDR was expressed by pQE40 procaryotic expression system,purified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis（SDS-PAGE） analysis with only one band and proved by Western blot.MTT assay demonstrateds that sKDR could inhibit the VEGF-stimulated HUVEC from proliferation,and CAM experiment showed sKDR could block the VEGF-induced angiogenesis.sKDR has the biological activity to bind with VEGF ligands and is a potential target for tumor anti-angiogenesis therapy.

miR-126阳离子纳米乳的制备及初步药效

目的采用阳离子纳米乳(CNE)载miRNA-126(miR-126)形成miR-126阳离子纳米乳递送系统(CNE-miR126),并对其药剂学性能、时间稳定性、血清稳定性、细胞毒性、细胞摄取及血管黏附分子-1(VCAM-1)蛋白表达量进行评估。方法用琼脂糖凝胶电泳考察CNE和miR-126的最佳氮磷比(N/P),采用纳米粒度及Zeta电位分析测量仪测定其粒径和进行药剂学性能评价;在4℃条件下,评估CNE-miR-126在1周内粒径及电位的稳定性;用血清稳定性实验评估CNE-miR-126在48 h之内的稳定性,MTT法评估CNE-miR-126的细胞毒性;流式细胞术和荧光显微镜观察人脐静脉内皮细胞(HUVECs)对CNE-miR-126的摄取情况,免疫蛋白质印迹法(Weston blot)检测CNE-miR-126对由脂多糖(LPS)致炎的HUVECs中VCAM-1的表达水平。结果CNE与miR-126最佳N/P为16∶1,CNE-miR-126外观基本圆整、平均粒径(D_(50))为(144.79±1.85)nm、Zeta电位为(22.92±1.24)mV;CNE-miR-126在1周内粒径及电位稳定性良好,且在48 h之内血清稳定性良好;在10^(-6)~1 nmol/L浓度内对HUVECs细胞生长无明显抑制作用,能够促进HUVECs对miR-126的摄取;Weston blot结果显示,与Control组相比,LPS(1 mg/L)处理细胞8 h后VCAM-1蛋白水平显著升高(P<0.01);与Model组相比,CNE-miR-126组预处理24 h后VCAM-1蛋白水平降低(P<0.05)。结论CNE-miR-126粒径适宜,稳定性良好,可降低VCAM-1蛋白的表达,可为心血管疾病的治疗提供参考。

Salidroside Ameliorates Vascular Endothelial Cell Senescence through Downregulation of KLF4

Salidroside is extensively used as a herbal medicine worldwide, and it has been shown to protect against disruption of endothelial homeostasis and act as an anti-aging agent. The present study aimed to investigate the ameliorative effects of salidroside on homocysteine (Hcy)-induced cell senescence in human umbilical vein endothelial cells (HUVECs) that were mediated via inhibition of Krüppel-like factor 4 (KLF4). An endothelial cell senescence model was induced by Hcy. The cell viability, activities of telomerase and lactate dehydrogenase (LDH), and the level of reactive oxygen species were determined using commercial kits. The expression levels of KLF4, p53 and p21 were determined via western blot analysis, whereas the mRNA expression levels of KLF4 were detected by reverse transcription-quantitative PCR. Small interfering RNA-mediated knockdown of KLF4 was found to reverse Hcy-induced cell senescence. Hcy treatment led to an accelerated cell senescence, as evidenced by decreases in both cell viability and telomerase activity, whereas increases were noted in the leakage of LDH and the level of reactive oxygen species, in addition to an up-regulation of the protein levels of p53 and p21, and up-regulation of KLF4 at both the mRNA and protein level. Treatment with salidroside ameliorated Hcy-induced cell senescence in a dose-dependent manner. Taken together, these results suggested that Hcy may induce cell senescence through upregulation of KLF4, and this may be reversed by treatment with salidroside. Therefore, salidroside was shown to inhibit Hcy-induced cell senescence through KLF4 inhibition.

High-density lipoprotein endocytosis in endothelial cells

AIM: To describe the way stations of high-density lipoprotein(HDL) uptake and its lipid exchange in endothelial cells in vitro and in vivo. METHODS: A combination of fluorescence microscopy using novel fluorescent cholesterol surrogates and electron microscopy was used to analyze HDL endocytosis in great detail in primary human endothelial cells. Further, HDL uptake was quantified using radio-labeled HDL particles. To validate the in vitro findings mice were injected with fluorescently labeled HDL and particle uptake in the liver was analyzed using fluorescencemicroscopy. RESULTS: HDL uptake occurred via clathrin-coated pits, tubular endosomes and multivesicular bodies in human umbilical vein endothelial cells. During uptake and resecretion, HDL-derived cholesterol was exchanged at a faster rate than cholesteryl oleate, resembling the HDL particle pathway seen in hepatic cells. In addition, lysosomes were not involved in this process and thus HDL degradation was not detectable. In vivo, we found HDL mainly localized in mouse hepatic endothelial cells. HDL was not detected in parenchymal liver cells, indicating that lipid transfer from HDL to hepatocytes occurs primarily via scavenger receptor, class B, type Ⅰ mediated selective uptake without concomitant HDL endocytosis. CONCLUSION: HDL endocytosis occurs via clathrincoated pits, tubular endosomes and multivesicular bodies in human endothelial cells. Mouse endothelial cells showed a similar HDL uptake pattern in vivo indicating that the endothelium is one major site of HDL endocytosis and transcytosis.

Culture supernatants of breast cancer cell line MDA-MB-231 treated with parthenolide inhibit the proliferation, migration, and lumen formation capacity of human umbilical vein endothelial cells

Background Parthenolide has been tested for anti-tumor activities, such as anti-proliferation and pro-apoptosis in recent studies. However, little is known about its role in the process of tumor angiogenesis. This study aims to investigate the effects and potential mechanisms of parthenolide on the proliferation, migration and lumen formation capacity of human umbilical vein endothelial cells. Methods Different concentrations of parthenolide were applied to the human breast cancer cell line MDA-MB-231 cells. After 24-hour incubation, the culture supernatants were harvested and used to treat human umbilical vein endothelial cells for 24 hours. Then an inverted fluorescence phase contrast microscope was used to evaluate the human umbilical vein endothelial cells. The secretion of vascular endothelial growth factor （VEGF）, interleukin （IL）-8 and matrix metalloproteinases （MMP）-9 in the culture supernatant of the MDA-MB-231 cells was then measured with enzyme-linked immunosorbent assay （ELISA） assays. Results Suppression of proliferation, migration, and the lumen formation capacity of human umbilical vein endothelial cells was observed in the presence of the culture supernatants from the breast cancer cell line treated with different concentrations of parthenolide. Parthenolide decreased the levels of the angiogenic factors MMP-9, VEGF, and IL-8 secreted by the MDA-MB-231 cells. Conclusions Parthenolide may suppress angiogenesis through decreasing angiogenic factors secreted by breast cancer cells to interfere with the proliferation, migration and lumen-like structure formation of endothelial cells, thereby inhibiting tumor growth. It is a promising potential anti-angiogenic drug.

Piper sarmentosum as an antioxidant on oxidative stress in human umbilical vein endothelial cells induced by hydrogen peroxide

Endothelial cell death due to increased reactive oxygen species(ROS) may contribute to the initial endothelial injury,which promotes atherosclerotic lesion formation.Piper sarmentosum(PS),a natural product,has been shown to have an antioxidant property,which is hypothesized to inhibit production of ROS and prevent cell injury.Thus,the present study was designed to determine the effects of PS on the hydrogen peroxide(H2O2)-induced oxidative cell damage in cultured human umbilical vein endothelial cells(HUVECs).In this experiment,HUVECs were obtained by collagenase perfusion of the large vein in the umbilical cord and cultured in medium M200 supplemented with low serum growth supplementation(LSGS).HUVECs were treated with various concentrations of H2O2(0-1000 μmol/L) and it was observed that 180 μmol/L H2O2 reduced cell viability by 50% as denoted by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay.Using the above concentration as the positive control,the H2O2-induced HUVECs were concomitantly treated with various concentrations(100,150,250 and 300 μg/ml) of three different extracts(aqueous,methanol and hexane) of PS.Malondialdehyde(MDA),superoxide dismutase(SOD),catalase(CAT) and glutathione peroxidase(GPX) levels showed a significant increase(P<0.05) in HUVECs compared to the negative control.However,PS extracts showed a protective effect on HUVECs from H2O2-induced cell apoptosis with a significant reduction in MDA,SOD,CAT and GPX levels(P<0.05).Furthermore,PS had exhibited ferric reducing antioxidant power with its high phenolic content.Hence,it was concluded that PS plays a beneficial role in reducing oxidative stress in H2O2-induced HUVECs.

Involvement of heme oxygenase-1 induction in anti-vascular inflammation effects of Xanthoceras sorbifolia in human umbilical vein endothelial cells

OBJECTIVE: To define the effects of Xanthoceras sorbifolia(EXS) on vascular inflammation and the mechanisms in endothelial cells.METHODS: Vascular protective effects of an ethanol extract of seeds from EXS(1-50 μg/mL) against tumor necrosis factor-α(TNF-α)-induced vascularinflammation were examined in human umbilical vein endothelial cells(HUVECs).RESULTS: EXS significantly decreased TNF-α-induced expression of cell adhesion molecules, such as intracellular adhesion molecule-1, vascular cell adhesion molecule-1, and endothelial cell selectin,in a dose-dependent manner. Pre-treatment with EXS significantly inhibited translocation and transcriptional activity of nuclear factor-κB(NF-κB) increased by TNF-α. EXS also significantly inhibited formation of intracellular reactive oxygen species(ROS). Moreover, the vascular protective effects of EXS were linked to up-regulation of heme oxygenase-1(HO-1) and nuclear factor E2-related factor-2(Nrf-2) expression. EXS-induced HO-1 expression was significantly decreased in SnPP(HO-1 inhibitor)-and HO-1 siRNA-treated cells, whereas an increase was found in cobalt protoporphyrin IX(CoPP)(HO-1 inducer)-treated cells. In addition, pretreatment with EXS increased HO-1 and Nrf-2 expression under TNF-α stimulation with or without N-acetyl-L-cysteine. Furthermore, the inhibitory effects of EXS on TNF-α-induced vascular inflammation were partially reversed in SnPP-and of HO-1siRNA-treated cells but increased by CoPP.CONCLUSION: These results suggest that EXS may have important implications for prevention of vascular complications associated with vascular inflammation by inhibition of the NF-κB/ROS pathway and activation of the Nrf-2/HO-1 pathway.