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.

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.

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.

Ginsenoside Rb1 Protects Human Umbilical Vein Endothelial Cells against High Glucose-Induced Mitochondria-Related Apoptosis through Activating SIRT3 Signalling Pathway

Objective:To investigate whether ginsenoside Rb1(Rb1)can protect human umbilical vein endothelial cells(HUVECs)against high glucose-induced apoptosis and examine the underlying mechanism.Methods:HUVECs were divided into 5 groups:control group(5.5 mmol/L glucose),high glucose(HG,40 mmol/L)treatment group,Rb1(50μmol/L)treatment group,Rb1 plus HG treatment group,and Rb1 and 3-(1 H-1,2,3-triazol-4-yl)pyridine(3-TYP,16μmol/L)plus HG treatment group.Cell viability was evaluated by cell counting kit-8 assay.Mitochondrial and intracellular reactive oxygen species were detected by Mito Sox Red mitochondrial superoxide indicator and dichloro-dihydro-fluorescein diacetate assay,respectively.Annexin V/propidium iodide staining and fluorescent dye staining were used to measure the apoptosis and the mitochondrial membrane potential of HUVECs,respectively.The protein expressions of apoptosis-related proteins[Bcl-2,Bax,cleaved caspase-3 and cytochrome c(Cyt-c)],mitochondrial biogenesis-related proteins[proliferator-activated receptor gamma coactivator 1-alpha,nuclear respiratory factor-1 and mitochondrial transcription factor A],acetylation levels of forkhead box O3 a and SOD2,and sirtuin-3(SIRT3)signalling pathway were measured by immunoblotting and immunoprecipitation.Results:Rb1 ameliorated survival in cells in which apoptosis was induced by high glucose(P<0.05 or P<0.01).Upon the addition of Rb1,mitochondrial and intracellular reactive oxygen species generation and malondialdehyde levels were decreased(P<0.01),while the activities of antioxidant enzymes were increased(P<0.05 or P<0.01).Rb1 preserved the mitochondrial membrane potential and reduced the release of Cyt-c from the mitochondria into the cytosol(P<0.01).In addition,Rb1 upregulated mitochondrial biogenesis-associated proteins(P<0.01).Notably,the cytoprotective effects of Rb1 were correlated with SIRT3 signalling pathway activation(P<0.01).The effect of Rb1 against high glucose-induced mitochondria-related apoptosis was restrained by 3-TYP(P<0.05 or P<0.01).Conclusion:Rb1 could protect HUVECs from high glucose-induced apoptosis by promoting mitochondrial function and suppressing oxidative stress through the SIRT3 signalling pathway.

Pro-angiogenic Activity of Notoginsenoside R1 in Human Umbilical Vein Endothelial Cells in vitro and in a Chemical-Induced Blood Vessel Loss Model of Zebrafish in vivo

Objective： This study aimed at investigating whether notoginsenoside R1 （R1）, a unique saponin found in Panax notoginseng could promote angiogenic activity on human umbilical vein endothelial cells （HUVECs） and elucidate their potential molecular mechanisms. In addition, vascular restorative activities of R1 was assessed in a chemically-induced blood vessel loss model in zebrafish. Methods： The in vitro angiogenic effect of R1 was compared with other previously reported angiogenic saponins Rgl and Re. The HUVECs proliferation in the presence of R1 was determined by cell proliferation kit lI （XTI＇） assay. R1, Rgl and Re-induced HUVECs invasion across polycarbonate membrane was stained with Hoechst-33342 and quantified microscopically. Tube formation assay using matrigel- coated wells was performed to evaluate the pro-angiogenic actions of RI. In order to understand the mechanism underlying the pro-angiogenic effect, various pathway inhibitors such as SU5416, wortmannin （wort） or L-N （o -nitro- L-arginine methyl ester hydrochloride （L-NAME）, SH-6 were used to probe the possible involvement of signaling pathway in the R1 mediated HUVECs proliferation. In in vivo assays, zebrafish embryos at 21 hpf were pre-treated with vascular endothelial growth factor （VEGF） receptor kinase inhibitor ]1 （VRI） for 3 h only and subsequently post-treated with R1 for 48 h, respectively. The intersegmental vessels （ISVs） in zebrafish were assessed for the restorative effect of R1 on defective blood vessels. Results： R1 could stimulate the proliferation of HUVECs. In the chemoinvasion assay, R1 significantly increased the number of cross-membrane HUVECs. In addition, R1 markedly enhanced the tube formation ability of HUVECs. The proliferative effects of these saponins on HUVECs were effectively blocked by the addition of SU5416 （a VEGF-KDR/FIk-1 inhibitor）. Similarly, pre-treatment with wort [a phosphatidylinositol 3-kinase （PI3K）-kinase inhibitor], L-NAME [an endothelial nitric oxide synthase （eNOS） inhibitor] or SH-6 （an Akt pathway inhibitor） significantly abrogated the R1 induced proliferation of HUVECs. In chemically- induced blood vessel loss model in zebrafish, R1 significantly rescue the damaged ISVs. Conclusion： R1, similar to Rgl and Re, had been showed pro-angiogenic action, possibly via the activation of the VEGF-KDR/FIk-1 and PI3K- Akt-eNOS signaling pathways. Our findings also shed light on intriguing pro-angiogenic effect of R1 under deficient angiogenesis condition in a pharmacologic-induced blood vessels loss model in zebrafish. The present study in vivo and in vitro provided scientific evidence to explain the ethnomedical use of Panax notoginseng in the treatment of cardiovascular diseases, traumatic injuries and wound healing.

Inhibitory Effect of Cryptotanshinone on Angiogenesis and Wnt/β-Catenin Signaling Pathway in Human Umbilical Vein Endothelial Cells

Objective：To investigate the anti-angiogenic effect of cryptotanshinone（CPT） on human umbilical vein endothelial cells（HUVECs） and the effect of CPT on Wnt/β-catenin signaling pathway.Methods：HUVECs were incubated with 0,2.5,5,10,and 20 μmol/L CPT for detecting cell viability with dimethyl thiazolyl-2,5-diphenyltetrazolium bromide（MTT） assay.Then,HUVECs were incubated with 0,2.5,5,and 10 μmol/L CPT for detecting endothelial cell migration,invasion,and tubular-like structure formation with wound healing,transwell invasion and matrigel tube formation assays,respectively.To gain insight into CPT-mediated signaling,the effects of CPT on T-cell factor/lymphocyte enhancer factor（TCF/LEF） transcription factors were detected by the Dual-luciferase reporter assay.Next,the nuclear expression of p-catenin was evaluated using Western blot and immunochemistry.Finally,vascular endothelial growth factor（VEGF） and cyclin D1,downstream proteins of the Wnt pathway were examined with Western blot.Results：CPT dose-dependently suppressed endothelial cell viability,migration,invasion,and tubular-like structure formation.In particular,CPT blocked β-catenindependent transcription in HUVECs in a dose-dependent manner.In Western bolt,10 μ mol/L CPT decreased expression of β-catenin in nucleus of HUVECs（P〈0.01）.In immunohistochemistry,β-catenin was more potent in response to LiCI（an activator of the pathway） treatment.However,the signals were weaker in the nucleus of the CPT（10 μmol/L） group,compared to the positive control.Also,VEGF and cyclin D1 were both eliminated by CPT in 5 and 10 μ mol/L doses（P〈0.05）.Conclosion：Our study supported the role of CPT as an angiogenic inhibitor,which may impact on the Wnt/β-catenin signaling pathway.

Paeoniflorin Promotes Angiogenesis in A Vascular Insufficiency Model of Zebrafish in vivo and in Human Umbilical Vein Endothelial Cells in vitro

Objective： To investigate the pro-angiogenic effects of paeoniflorin（PF） in a vascular insufficiency model of zebrafish and in human umbilical vein endothelial cells（HUVECs）. Methods： In vivo, the pro-angiogenic effects of PF were tested in a vascular insufficiency model in the Tg（fli-1：EGFP）y1 transgenic zebrafish. The 24 h post fertilization（hpf） embryos were pretreated with vascular endothelial growth factor（VEGF） receptor tyrosine kinase inhibitor Ⅱ（VRI） for 3 h to establish the vascular insufficiency model and then post-treated with PF for 24 h. The formation of intersegmental vessels（ISVs） was observed with a fluorescence microscope. The m RNA expression of fms-like tyrosine kinase-1（flt-1）, kinase insert domain receptor（kdr）, kinase insert domain receptor like（kdrl） and von Willebrand factor（v WF） were analyzed by real-time polymerase chain reaction（PCR）. In vitro, the pro-angiogenic effects of PF were observed in HUVECs in which cell proliferation, migration and tube formation were assessed. Results： PF（6.25–100 μmol/L） could rescue VRI-induced blood vessel loss in zebrafish and PF（25–100 μmol/L）, thereby restoring the m RNA expressions of flt-1, kdr, kdrl and v WF, which were down-regulated by VRI treatment. In addition, PF（0.001–0.03 μmol/L） could promote the proliferation of HUVECs while PF stimulated HUVECs migration at 1.0–10 μmol/L and tube formation at 0.3 μmol/L. Conclusion： PF could promote angiogenesis in a vascular insufficiency model of zebrafish in vivo and in HUVECs in vitro.

Effect of Xuefu Zhuyu Decoction (血府逐瘀汤) on the Function of Platelets and Human Umbilical Vein Endothelial Cell

Objective: To explore the effect of Xuefu Zhuyu Decoction (XZD) on molecular expression of platelets glycoprotein Ⅱb/Ⅲa complex (GP Ⅱb/Ⅲa) and thrombomodulin (TM) of human umbilical vein endothelial cells.Methods: Platelets and human umbilical vein endothelial cells were incubated with XZD of different concentration. GPⅡb/Ⅲa and TM were evaluated by radioimmunoassay.Results: XZD in 40 mg/ml and 80 mg/ml could obviously inhibit the adenosine diphosphate induced GPⅡb/Ⅲa complex expression, the molecular number being 52900±8445 and 52095±6345 respectively, and there was significant difference as comparing with that in the control group (P<0.05, P<0.01). But XZD didn't show any influence on the molecular expression of TM in human umbilical vein endothelial cells.Conclusion: XZD could inhibit the adenosine diphosphate induced activation of platete through blocking the exposure of GPⅡb/Ⅲa complex.

Cardiotrophin-1 induces intercellular adhesion molecule-1 expression by nuclear factor κB activation in human umbilical vein endothelial cells

Background In addition to elevated concentrations of cytokines, patients with congestive endothelial dysfunction and increased plasma concentrations of adhesion molecules heart failure （CHF） show ke intercellular adhesion molecule-1 （ICAM-1）. Furthermore, the concentration of cardiotrophin-1 （CT-1） - a cytokine of the interleukin-6 superfamily - is increased in CHF. We tested the hypothesis whether CT-1 is able to induce ICAM-1 in human umbilical vein endothelial cells （HUVEC）. Furthermore we examined the signalling mechanisms of CT-1 mediated ICAM-1 expression. Methods Confluent layers of HUVEC were incubated with increasing concentrations of CT-1 （5 to 100 ng/ml） for different periods. ICAM-1 mRNA was determined by real-time polymerase chain reaction （PCR） and ICAM-1 surface expression by fluorescence-activated cell sorter （FACS） analysis and soluble ICAM-1 （slCAM-1） in the culture supernatant by enzyme linked immunosorbent assay （ELISA）. To clarify the signalling pathway of CT-1 induced ICAM-1 expression we used various inhibitors of possible signal transducing molecules, electromobility shift assay （EMSA） and Western blot analysis. Results CT-1 induced ICAM-1 mRNA （1.8±0.8 fold increase compared to unstimulated cells after 6 hours） and protein （1.4±0.2 fold increase compared to unstimulated cells after 48 hours） in HUVEC in a time- and concentration-dependent manner. EMSA experiments show that CT-1 causes nuclear factor （NF） κB activation. Because parthenolide could inhibit CT-1 induced ICAM-1 expression NFκB activation is required in this pathway. CT-1 did not activate extracellular signal regulated kinases （ERK）, c-Jun N-terminal kinase （JNK） and p38. Conclusion CT-1 is able to induce ICAM-1 in endothelial cells by NFκB activation. These results may explain in part elevated ICAM-1 concentrations in patients with CHF and endothelial dysfunction.

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.

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.

Hypoxia Downregulates the Angiogenesis in Human Placenta via Notch1 Signaling Pathway

Placentation, which is critical for maternal-fetal exchange of nutrients and gases, is a complicated process comprising stepwise vasculogenesis and angiogenesis. Hypoxia caused by impaired trophoblast invasion may cause various angiogenic abnormalities in human placenta. The Notch1 signaling pathway plays an important role in the regulation of angiogenesis. The angiogenesis of human umbilical vein endothelial cells（HUVECs） under normal/hypoxic conditions and the m RNA/protein level of Notch1/Dell4/Jagged1 were investigated in this study. The effects of DAPT/JAG-1 on the migration of HUVECs were also assessed by cell wound healing assay, so as to discover the possible role of notch1 signaling pathway in the angiogenesis of human placenta. The results showed that angiogenic ability of HUVECs was seriously reduced under hypoxic conditions. The m RNA and protein levels of Notch1/Dell4/Jagged1 were decreased in the hypoxic group compared to the control one. In addition, the migration capability of HUVECs was significantly obstructed when treated with DAPT and under hopoxic condition, but promoted when treated with JAG-1. The above results demonstrate that hypoxia downregulates the angiogenesis in human placenta via Notch1 signaling pathway.

A facile cell culture device for studying nuclear and mitochondrial response of endothelial cells to hydrostatic pressure

There is no clear consensus regarding how cells respond to hydrostatic pressure. This is largely attributable to the high heterogeneity among cell types and the diverse custom-made devices used in previous studies. The aim of this work was to develop a facile device that could mimic various pressure environments and then delineate the cellular response to pressure stimulus. The device described here achieved both stable and periodic pressurization without oxygen deprivation. The biological utility of the device was assessed using human umbilical vein endothelial cells. We found more stereoscopic nuclear morphology and re-distribution of lamin A/C under high hydrostatic pressure compared to control cells. Mass spectrometry-based proteomics analysis showed significant changes in mitochondria-related pathways. Western blot analysis confirmed that high hydrostatic pressure induced a tendency toward mitochondrial fusion. Increased mitochondrial activity was observed as well. In conclusion, this device can be readily applied in biological research and extend our understanding of cellular mechano-sensation and the associated changes in mitochondrial behaviors.

LncRNA HCG27 Promotes Glucose Uptake Ability of HUVECs by MiR-378a-3p/MAPK1 Pathway

Objective:Gestational diabetes mellitus(GDM)is the most common metabolic disorder during pregnancy.LncRNA HLA complex group 27(HCG27)plays a crucial role in various metabolic diseases.However,the relationship between lncRNA HCG27 and GDM is not clear.This study aimed to verify a competing endogenous RNA(ceRNA)interaction regulation axis of miR-378a-3p/mitogen-activated protein kinase 1(MAPK1)regulated by HCG27 in GDM.Methods:LncRNA HCG27 and miR-378a-3p were detected by RT-qPCR.The expression of MAPK1 in umbilical vein endothelial cells(HUVECs)was detected by RT-qPCR and that in the placenta by Western blotting.To explore the relationship among lncRNA HCG27,miR-378a-3p,MAPK1 and the glucose uptake ability of HUVECs,vector HCG27,si-HCG27,miR-378a-3p mimic and inhibitor were transfected to achieve overexpression and inhibition of HCG27 or miR-378a-3p.The interaction between miR-378a-3p and lncRNA HCG27 or MAPK1 was confirmed by the dual-luciferase reporter assay.Besides,glucose consumption by HUVECs was detected by the glucose assay kit.Results:HCG27 expression was significantly decreased in both the placenta and primary umbilical vein endothelial cells,while the expression of miR-378a-3p was significantly increased in GDM tissues,and the expression of MAPK1 was decreased in GDM tissues.This ceRNA interaction regulation axiswas proved to affect the glucose uptake function of HUVECs.The transfection of si-HCG27 could significantly reduce the expression of the MAPK1 protein.If the MAPK1 overexpression plasmid was transfected simultaneously with si-HCG27 transfection,the reduced glucose uptake in HUVECs resulting from the decrease in lncRNA HCG27 was reversed.MiR-378a-3p mimic can significantly reduce the mRNA expression of MAPK1 in HUVECs,whereas miR-378a-3p inhibitor can significantly increase the mRNA expression of MAPK1.The inhibition of miR-378a-3p could restore the decreased glucose uptake of HUVECs treated with si-HCG27.Besides,overexpression of lncRNA HCG27 could restore the glucose uptake ability of the palmitic acid-induced insulin resistance model of HUVECs to normal.Conclusion:LncRNA HCG27 promotes glucose uptake of HUVECs by miR-378a-3p/MAPK1 pathway,which may provide potential therapeutic targets for GDM.Besides,the fetal umbilical cord blood and umbilical vein endothelial cells collected from pregnant women with GDM after delivery could be used to detect the presence of adverse molecular markers of metabolic memory,so as to provide guidance for predicting the risk of cardiovascular diseases and health screening of offspring.

Tanshinone ⅡA Protects against Lipopolysaccharides-lnduced Endothelial Cell Injury via Rho/Rho Kinase Pathway

Objective： To test whether tanshinone ⅡA （Tan ⅡA）, a highly valued herb derivative to treat vascular diseases in Chinese medicine, could protect endothelial cells from bacterial endotoxin （lipopolysaccharides, LPS）-induced endothelial injury. Methods： Endothelial cell injury was induced by treating human umbilical vein endothelial cells （HUVECs） with 0.2 μg/mL LPS for 24 h. Y27632 and valsartan were used as positive controls. The effects of tanshinone Ⅱ A on the LPS-induced cell viability and apoptosis rate of HUVECs were tested by flow cytometry, cell migration by transwell, adhesion by a 96-well plate pre-coated with vitronectin and cytoskeleton reorganization by immunofluorescence assay. Rho/Rho kinase （ROCK） pathway- associated gene and protein expression were examined by microarray assay; quantitative real-time polymerase chain reaction and Western blotting were used to confirm the changes observed by microarray. Results： Tan ][ A improved cell viability, suppressed apoptosis and protected cells from LPS-induced reductions in cell migration and adhesion at a comparable magnitude to that of Y27632 and valsartan. Tan II A, Y27632 and valsartan also normalized LPS-induced actomyosin contraction and vinculin protein aggregation. A microarray assay revealed increased levels of fibronectin, integrin A5 （ITG A5）, Ras homolog gene family member A （RheA）, myosin light chain phosphatase, phosphatidylinositol-4,5-bisphosphate 3-kinase （PI3K, or PIP2 in Western blotting）, focal adhesion kinase, vascular endothelial growth factor and vascular endothelial growth factor receptor 2 in the damaged HUVECs, which were attenuated to different degrees by Tan ⅡA, Y27632 and valsartan. Conclusion： Tan ⅡA exerted a strong protective effect on HUVECs, and the mechanism was caused, at least in part, by a blockade in the Rho/ROCK pathway, presumably through the down-regulation of ITG A5.