Vein Endothelial Cell Cultures Research Articles

Generalized Multifunctional Coating Strategies Based on Polyphenol-Amine-Inspired Chemistry and Layer-by-Layer Deposition for Blood Contact Catheters.

Blood-contacting catheters play a pivotal role in contemporary medical treatments, particularly in the management of cardiovascular diseases. However, these catheters exhibit inappropriate wettability and lack antimicrobial characteristics, which often lead to catheter-related infections and thrombosis. Therefore, there is an urgent need for blood contact catheters with antimicrobial and anticoagulant properties. In this study, we employed tannic acid (TA) and 3-aminopropyltriethoxysilane (APTES) to create a stable hydrophilic coating under mild conditions. Heparin (Hep) and poly(lysine) (PL) were then modified on the TA-APTES coating surface using the layer-by-layer (LBL) technique to create a superhydrophilic TA/APTES/(LBL)4 coating on silicone rubber (SR) catheters. Leveraging the superhydrophilic nature of this coating, it can be effectively applied to blood-contacting catheters to impart antibacterial, antiprotein adsorption, and anticoagulant properties. Due to Hep's anticoagulant attributes, the activated partial thromboplastin time and thrombin time tests conducted on SR/TA-APTES/(LBL)4 catheters revealed remarkable extensions of 276 and 103%, respectively, when compared to uncoated commercial SR catheters. Furthermore, the synergistic interaction between PL and TA serves to enhance the resistance of SR/TA-APTES/(LBL)4 catheters against bacterial adherence, reducing it by up to 99.9% compared to uncoated commercial SR catheters. Remarkably, the SR/TA-APTES/(LBL)4 catheter exhibits good biocompatibility with human umbilical vein endothelial cells in culture, positioning it as a promising solution to address the current challenges associated with blood-contact catheters.

Abstract 3559: Galectin-1 upregulates CXCR4 in glioblastoma through upregulation of CXCR4 via NF-κB activation

Abstract Background: Despite aggressive treatment, including surgical resection, radiation and chemotherapy, over 90% of glioblastoma (GB) patients experience tumor recurrence. This may be due to high migratory potential, abnormal angiogenesis, molecular heterogeneity and a strong immunosuppressive environment. An earlier report from our laboratory demonstrated that GB cells express high levels of carbohydrate-binding galectin protein: galectin-1 (Gal-1). However, the role of galectin-1 in GB remains elusive. The aim of this study was to evaluate whether galectin-1 promotes tumor progression through upregulation of CXCR4 via NF-κB in in vitro GB models. Methods: To investigate the molecular mechanisms of Gal-1 on tumor progression, we used RT-PCR and western blots techniques. Gal-1 was stably over-expressed in the U118 and U87MG cell line. Gal-1 (+/-) sub-clones were assayed for attachment, proliferation, migration, and tube formation. Results: Gal-1 protein expression was assessed in human GB cells. We found increased Gal-1 protein expression in human GB cells and tissue. To investigate the effects of Gal-1 silencing on angiogenesis in vitro, we collected conditioned media from Gal-1-knockdown U118 and U87MG cells then applied this to human umbilical vein endothelial cells (HUVEC) culture to analyze endothelial cell proliferation, migration, and tube formation. Proliferation rate, migrating capability, and tube formation decreased significantly when HUVECs were cultured with concentrated conditioned media from Gal-1-knockdown cells. This data suggests that Gal-1 in GB cells may promote tumor angiogenesis both in vitro and co-culture. Results showed that silencing of Gal-1 in U118 and U87MG cells significantly repressed CXCR4 expression at the mRNA level and protein levels. To further explore the role of CXCR4 in GB cells, CXCR4 knockdown resulted in significant inhibition of cell migration and clonogenic ability in vitro. Thus, Gal-1 might upregulate CXCR4 expression to promote tumor progression. A previous laboratory study indicated that NF-κB promotes cancer cell motility by upregulating CXCR4 expression. Luciferase reporter assay was used to determine the involvement of NF-κB in Gal-1-induced CXCR4 expression in U118 and U87MG cells. NF-κB luciferase activity was significantly decreased in Gal-1-knockdown cells. Moreover, decreased CXCR4 promoter activity and protein expression in Gal-1-knockdown cells were observed. This data indicates that Gal-1 might modulate CXCR4 expression via NF-κB activation. Conclusion: Our in vitro cell culture results suggest that upregulation of galectin-1 and CXCR4 might at least in part explain the aggressive infiltrative biology of GB and the Gal-1-CXCR4 axis may serve as a therapeutic target. Further studies in different animal models are warranted. Citation Format: David Cachia, Rachel Malley, William A. Vandergrift, Sunil Patel, Gabriel A. Rabinovich, Arabinda Das. Galectin-1 upregulates CXCR4 in glioblastoma through upregulation of CXCR4 via NF-κB activation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3559.

Anti-angiogenic effect of chebulagic acid involves inhibition of the VEGFR2- and GSK-3β-dependent signaling pathways.

Inhibition of angiogenesis is a useful strategy to prevent cancer growth by targeting new vessels that grow to nourish actively proliferating tumor cells. Endothelial cells can use a number of different pathways to cause angiogenesis, and each step in these pathways can be targeted. The use of multi-targeted drugs is gaining much importance in this scenario. Our previous results have shown that chebulagic acid (a benzopyran tannin present in the fruits of Terminalia chebula) has anti-angiogenic properties. Thus, this study was designed to examine the molecular mechanism for the anti-angiogenic effects of chebulagic acid. Results from our investigations using molecular docking studies and human umbilical vein endothelial cells in culture suggested that chebulagic acid inhibits both GSK-3β-dependent β-catenin phosphorylation (an important mediator of VE-cadherin-β-catenin signaling) and VEGFR2 phosphorylation, which is an important step in VEGF signaling. Chebulagic acid inhibits angiogenesis by blocking both the VEGF-VEGFR2 complex and cell-cell contact dependent downstream signaling pathways.

Abstract 227: Leptin induces a fibroblast and endothelial cell crosstalk in tumor stroma

Abstract Background: The tissue microenvironment plays a major role in tumor development and recurrence. It is known that leptin secreted by cancer and adipose cells can modify the tumor stroma, which is composed of immune, fibroblast, and endothelial cells (EC). Leptin affects both normal and cancer associated fibroblasts. We have previously shown that leptin can modify EC directly via an increase of angiogenic features; which was linked to VEGFR signaling and Notch expression independent of VEGF. It is hypothesized that leptin induces a communication between fibroblast and endothelial cells via induction of Notch signaling, which may be related to exosome production. Methods: Non-expressing Ob-R fibroblasts, and fibroblasts transfected with Ob-R plasmid, were used to investigate leptin's actions on Notch activation. Fibroblasts were challenged with leptin (0.6, 1.2, 6.2 nM) and an inhibitor of Notch signaling activation (DAPT). Fibroblast culture supernatants were added to and human umbilical vein endothelial cells (HUVEC) cultures. Notch proteins and RNA expression and molecular markers of activated fibroblasts and derived exosomes were determined via Western blot, RT-PCR, and multiplex analyses, respectively. EC angiogenic features were also determined. Results: Our findings suggest that leptin induces fibroblast activation, which triggers the expression of Notch and the development of angiogenic features by EC. Conclusions: A novel mechanism is proposed by which leptin promotes tumor stroma development via Notch activation and a crosstalk between fibroblasts and EC. Cancer therapies targeting leptin signaling could be a new strategy for interfering with cellular processes that promotes changes of tumor stroma towards a more aggressive tumor environment. Citation Format: Viola Lanier. Leptin induces a fibroblast and endothelial cell crosstalk in tumor stroma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 227.

Effects of Danhong Injection (丹红注射液) and its main components on anticoagulation and fibrinolysis in cultured vein endothelial cells

To observe the effects of Danhong Injection (丹红注射液) and its main components, including daiclzein and hydroxysafflor yellow A (HSYA), on the anticoagulation, fibrinolysis, anti-apoptosis in hypoxia model of vein endothelial cells (VECs). VECs were prepared and were put in a hypoxia environment, which consisted of mixed gas of 95% N and 5% CO mixed gas, when reached confluent culture. Five groups used different treatments, including normal control group, hypoxia group, daiclzein group, HSYA group and Danhong Injection group. The VECs were identified by fluorescence double labeling methods. The morphology was observed by a phase contrast microscopy. The effects of Danhong Injection, daiclzein and HSYA on 6 keto prostaglandin F1α (6-keto-PGF1α) level was measured by the method of radioimmunoassay (RIA). Superoxide dismutase (SOD) activity was tested by water soluble tetrazolium salt. The content of malondialdehyde (MDA) was measured by thiobarbituric acid. The activities of tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI) were measured by the method of chromogenic substrate. The contents of endothelin (ET) and nitric oxide (NO) were detected by non-equilibrium RIA and enzymelinked immunosorbent assay. Cells apoptosis rate was determined by flow cytometry. Compared with the normal control group, the floating cells number, PAI activity, ET and MDA contents, and cells apoptosis rate in the culture solution of hypoxia group were all significantly increased, whereas the 6-keto-PGF1α and NO contents, and t-PA and SOD activities were decreased significantly (P<0.01). Compared with the hypoxia group, Danhong Injection markedly increased the 6-keto-PGF1α content and SOD activity, regulated PAI and t-PA activities, ET and NO contents, and decreased MDA content and cells apoptosis rate (P<0.05 or P<0.01). Danhong Injection and its main components played an important role in protecting primary VECs from hypoxic damage by regulating the secretion and vasomotor function of VECs. The function of Danhong Injection was most remarkable.

Aged garlic extract enhances heme oxygenase-1 and glutamate-cysteine ligase modifier subunit expression via the nuclear factor erythroid 2–related factor 2–antioxidant response element signaling pathway in human endothelial cells

The nuclear factor erythroid 2–related factor 2 (Nrf2)–antioxidant response element (ARE) pathway defends cells against oxidative stress and regulates the cellular redox balance. Activation of this pathway induces a variety of antioxidant enzymes, resulting in the protection of our bodies against oxidative damage. It has been reported that aged garlic extract (AGE), a garlic preparation that is rich in water-soluble cysteinyl moieties, reduces oxidative stress and helps to ameliorate of cardiovascular, renal and hepatic diseases. We hypothesized that AGE enhances the expression of antioxidant enzymes via the Nrf2-ARE pathway in human umbilical vein endothelial cells in culture. Gene expression of antioxidant enzymes was measured using real-time polymerase chain reaction. Nuclear accumulation of Nrf2 and antioxidant enzymes expression were evaluated using western blotting analyses. We found that AGE promoted the accumulation of Nrf2 into the nucleus in a time- and dose-dependent manner and increased the gene expression and polypeptide level of heme oxygenase-1 (HO-1) and glutamate-cysteine ligase modifier subunit (GCLM). Moreover, the effect of AGE in elevating the gene expression of HO-1 and GCLM was found to be mediated via Nrf2 activation in human umbilical vein endothelial cells. Taken together, these observations suggest that AGE induces the expression of HO-1 and GCLM, which are antioxidant enzymes, via activation of the Nrf2-ARE signaling pathway.

The effects of biogenic and abiogenic disulphides on endothelial cells in culture: Comparison of three methods of viability assessment

Effects of biogenic and abiogenic disulphides on viability of human umbilical vein endothelial cells in culture has been investigated using three methods: the neutral red uptake assay, quantification of intracellular ATP, and modifications of Mosmann method, the essence of which is the reduction of tetrazolium salts, MTT and MTS, by cells. 2,2'-dithio-bis(N,N-diethyl)ethanamine (DS) was used as an abiogenic disulphide. As for biogenic disulphides, we used GSSG and garlic oil (GO), the principal component of which is diallyl disulphide (DADS). It has been found that DS and GO have a similar cytotoxic effect upon the endothelial cells (EC50 - 0.6 mM). GSSG in concentrations up to 1 mM did not effect the viability of endothelial cells. It has been demonstrated for the first time that DS and GO can serve as mediators of plasma membrane oxidoreductase activity, tetrazolium salts being as the substrate; this may cause false-negative effect. Thus, the Mosmann method has serious limitations when testing the cytotoxicity of disulphides, though can be used in studying the mechanism of action of disulphides.

Toxic effects of xylazine on endothelial cells in combination with cocaine and 6-monoacetylmorphine

The use of xylazine as a drug of abuse has emerged worldwide in the last 7years, including Puerto Rico. Clinical findings reported that xylazine users present greater physiological deterioration, than heroin users. The aim of this study was to assess the xylazine toxicity on endothelial cells, as this is one of the first tissues impact upon administration. Human umbilical vein endothelial cells in culture were treated with xylazine, cocaine, 6-monoacetylmorphine (heroin metabolite) and its combinations, at concentrations of 0.10–400μM, for periods of 24, 48 and 72h. IC50 were calculated and the Annexin V assay implemented to determine the cell death mechanism. Results indicated IC50 values at 24h as follow: xylazine 62μM, cocaine 210μM, 6-monoacetylmorphine 300μM. When these drugs were combined the IC50 value was 57μM. Annexin V results indicated cell death by an apoptosis mechanism in cells treated with xylazine or in combination. Results demonstrated that xylazine use inhibits the endothelial cell proliferation, at lower concentrations than cocaine and 6-monoacetylmorphine. These findings contribute to the understanding of the toxicity mechanisms induced by xylazine on endothelial cells.

Serum-dependence of affinity-mediated VEGF release from biomimetic microspheres.

Vascular endothelial growth factor (VEGF) activity is highly regulated via sequestering within the ECM and cell-demanded proteolysis to release the sequestered VEGF. Numerous studies have demonstrated that VEGF activity mediates cellular events leading to angiogenesis and capillary formation in vivo. This has motivated the study of biomaterials to sustain VEGF release, and in many cases, the materials are inspired by the structure and function of the native ECM. However, there remains a need for materials that can bind to VEGF with high specificity, as the in vivo environment is rich in a variety of growth factors (GFs) and GF-binding moieties. Here we describe a strategy to control VEGF release using hydrogel microspheres with tethered peptides derived from VEGF receptor 2 (VEGFR2). Using biomaterials covalently modified with varying concentrations of two distinct VEGFR2-derived peptides with varying serum stability, we analyzed both biomaterial and environmental variables that influence VEGF release and activity. The presence of tethered VEGF-binding peptides (VBPs) resulted in significantly extended VEGF release relative to control conditions, and the resulting released VEGF significantly increased the expansion of human umbilical vein endothelial cells in culture. VEGF release rates were also strongly influenced by the concentration of serum. The presence of Feline McDonough Sarcoma-like tyrosine kinase 1 (sFlt-1), a serum-borne receptor fragment derived from VEGF receptor 1, increased VEGF release rates, although sFlt-1 was not sufficient to recapitulate the release profile of VEGF in serum. Further, the influence of serum on VEGF release was not due to protease activity or nonspecific VEGF interactions in the presence of serum-borne heparin. VEGF release kinetics correlated well with a generalizable mathematical model describing affinity-mediated release of VEGF from hydrogel microspheres in defined conditions. Modeling results suggest a potential mechanism whereby competition between VEGF and multiple VEGF-binding serum proteins including sFlt-1, soluble kinase insert domain receptor (sKDR), and α2-macroglobulin (α2-M) likely influenced VEGF release from microspheres. The materials and mathematical model described in this approach may be useful in a range of applications in which sustained, biologically active GF release of a specific GF is desirable.

Endogenous controls in human umbilical vein endothelial cells under metabolic and oxidative stress

Background Gene expression studies on the effect of hypoxia and hyperglycemia using human umbilical vein endothelial cell (HUVEC) cultures are of particular interest in cardiovascular disease and diabetes. Normalization of gene expression data refers to the comparison of expression values using endogenous control that is steady across independent experimental conditions, a crucial step for gene expression studies. The endogenous controls for experiments involving hyperglycemia, hypoxia and a combination of the two have not been identified before in HUVEC. Our objective was to identify endogenous controls that are stable under oxidative (hypoxia) and metabolic stress (hyperglycemia) in HUVEC.

The role of fucosylation in the promotion of endothelial progenitor cells in neovascularization and bone repair

Bone marrow-derived endothelial progenitor cells (EPCs) are being tested as a therapy to treat a variety of ischemic diseases. Poor homing to targeted tissues is one of the major factors limiting the therapeutic efficacy of EPCs. Here, we show that human cord blood-derived EPCs expressed little sialyl Lewis X (sLex) antigen that is necessary for selectin-mediated cell–cell interactions. Expression of α1,3-fucosyltransferase VI (FucT VI) in the EPCs enhanced sLex synthesis, E- and P-selectin-binding, and EPC adhesion to tumor necrosis factor-α-stimulated human umbilical vein endothelial cells in culture. In a mouse model of hind limb ischemia, in which EPCs were injected intravenously, FucT VI expression increased EPC homing, neovascularization, and blood flow in ischemic muscles. In another mouse model of femoral fracture, FucT VI-expressing EPCs were more efficient than control EPCs in targeting to peri-fracture tissues to enhance angiogenesis, blood flow and bone repair. These results indicate that fucosylated EPCs may be used to as an improved cellular source to treat ischemic diseases.

Hydrogen peroxide modulates expression of surface antigens by human umbilical vein endothelial cells in vitro

The aim of this study was to determine the immunological phenotype of human umbilical vein endothelial cells in culture and dynamics of expression of inducible CD molecules of the endothelial cell surface exposed to hydrogen peroxide (H2O2, 100–300 μM) in vitro. PMA was applied as a positive control. There was an insignificant increase (9–21%) of CD31 expression 3 h after the addition of H2O2 to the culture medium, statistically significant decrease of CD309 expression upon exposure to 200 and 300 μM H2O2, whereas a day after the addition of H2O2 we found a strongly pronounced dose-dependent increase of CD54 expression, as well as a moderate enhancement of the expression of all CD molecules.

Abstract 116: Slit-Robo Signaling Regulates Lipopolysaccharide-induced Endothelial Inflammation and Expression of Slit/Robo is Dysregulated During Endotoxemia

Abstract Introduction: Lipopolysaccharide (LPS) is one of the critical factors which induce endothelial inflammation during the pathogenesis of atherosclerosis, endocarditis and sepsis shock induced heart injury. The secretory Slit2 protein and its endothelial receptors Robo1 and Robo4 have been shown to regulate mobility and permeability of endothelial cells, which could be functional in regulating LPS induced endothelial inflammation. Hypothesis: We hypothesized that in addition to regulating permeability and migration of endothelial cells, Slit2-Robo1/4 signaling might regulate other LPS-induced endothelial inflammatory responses. Methods and Results: Using Human Umbilical Vein Endothelial Cells (HUVEC) culture, we observed that Slit2 treatment suppressed LPS-induced secretion of pro-inflammatory cytokines (including GM-CSF), cell adhesion molecule upregulation and monocyte (THP-1 cell) adhesion. With siRNA knock down techniques, we further confirmed that this anti-inflammatory effect is mediated by the interaction of Slit2 with its dominant receptor in endothelial cells, Robo4, though the much lesser expressed minor receptor Robo1 is pro-inflammatory. Our signaling studies showed that downstream of Robo4, Slit2 suppressed inflammatory gene expression by inhibiting the Pyk2 - NF-kB pathway following LPS-TLR4 interaction. In addition, Slit2 can induce a positive feedback to its expression and downregulate the pro-inflammatory Robo1 receptor via mediation of miR-218. Moreover, both in in vitro studies using HUVEC and in vivo mouse model studies indicated that LPS also causes endothelial inflammation by downregulating the anti-inflammatory Slit2 and Robo4 and upregulating the pro-inflammatory Robo1 during endotoxemia, especially in mouse arterial endothelial cells and whole heart. Conclusions: Slit2-Robo1/4 signaling is important in regulation of LPS induced endothelial inflammation, and LPS in turn causes inflammation by interfering with the expression of Slit2, Robo1 and Robo4. This implies that Slit2-Robo1/4 is a key regulator of endothelial inflammation and its dysregulation during endotoxemia is a novel mechanism for LPS induced cardiovascular pathogenesis.

Abstract 377: Development of a Cell-Based Assay for In Vitro Assessment of Ultrasound Enhanced Bevacizumab Release from Echogenic Liposomes for Delivery into Atherosclerotic Adventitia

Introduction. Vascular endothelial growth factor (VEGF) is an important mediator of angiogenesis, not only in tumor growth, but also in vulnerable atheroma progression. Recent research has indicated that bevacizumab, an anti-cancer monoclonal antibody targeting VEGF, can inhibit atheroma progression. We have developed bevacizumab-loaded echogenic liposomes (BEV-ELIP) as an ultrasound-triggered intrinsically targeted controlled release vehicle for treatment of developing atheroma. Hypothesis. PMA-treated human umbilical vein endothelial cell (HUVEC) cultures can serve as a means of optimizing BEV-ELIP inhibition. Methods. Bevacizumab (1 μg/ml) was added to 18-hour HUVEC cultures in 96-well plates, followed by 10 nM phorbol 12-myristate 13-acetate (PMA) 4 hours later and incubated for 24 hours. Controls consisted of no PMA, no BEV; no PMA + BEV; and no BEV + PMA. Cells were enumerated using a hemacytometer and tetrazolium dye MTT. Results. PMA enhanced cell proliferation by 21-50% relative to control cultures, but bevacizumab treatment of PMA cultures inhibited cell proliferation by 30-55%, to levels lower than no PMA + BEV controls (Fig. 1). Cell proliferative effects were paralleled by both cell-associated and secreted VEGF levels (determined by western blot and ELISA, respectively). Conclusions. We have developed an in vitro cell-based assay for testing BEV-ELIP efficacy with and without ultrasound pretreatment, involving addition of a BEV-containing sample before PMA and determining the inhibition of cell proliferation. This allows us to optimize our therapeutic prior to testing in an in vivo developing atheroma model.

Constant or fluctuating hyperglycemias increases cytomembrane stiffness of human umbilical vein endothelial cells in culture: roles of cytoskeletal rearrangement and nitric oxide synthesis

BackgroundPrevious studies have implicated continuous or intermittent hyperglycemia in altered endothelium-derived nitric oxide (NO) synthesis. NO can regulate both the F-actin cytoskeleton and endothelial cell membrane stiffness. Atomic force microscopy (AFM) is a powerful tool that can be used to study plasma membrane deformability at the single cell level. As membrane stiffness is partially dependent on filamentous F-actin, the interdependence of these parameters can be studied through the combined approaches of AFM and laser scanning confocal microscopy (LSCM). In the present study, we evaluated the effects of constant or fluctuating hyperglycemia on endothelial-derived NO synthesis, the cytoskeletal contribution and endothelial cell membrane stiffness.ResultsCompared to control cells cultured in low glucose (5 mM), constant (25 mM) or fluctuating (25/5 mM) high glucose significantly decreased NO release along with stiffening of endothelial cell membranes and F-actin rearrangement. The non-selective nitric oxide synthase (NOS) inhibitor, NG-nitro-L-arginine methyl ester (L-NAME) exerted similar effects on endothelial cells. Increasing concentrations of L-NAME (from 0.1 to 1 mM) exacerbated these effects in a concentration-dependent manner.ConclusionsResult from the present study suggest that stiffening endothelial cell membranes are associated with decreased NO synthesis, which was established through the F-actin cytoskeletal redistribution. The precise mechanisms of hyperglycemia-induced endothelial dysfunction require further investigation.

Understanding the STIM1-ulous

Signal Transduction![Figure][1] CREDIT: ALEJANDRO P. ADAM, PETER A. VINCENT, AND MOHAMED TREBAK The permeability of the circulatory system is carefully regulated, and disruption of the barrier can contribute to inflammation and sepsis. One important means of regulation is the action of thrombin on vascular endothelial cells. The receptor for thrombin initiates mobilization of calcium from intracellular stores, and Shinde et al. examined the role of such signaling in control of the endothelial barrier formed by human umbilical vein endothelial cells in culture. Signals that cause emptying of calcium stores lead to calcium entry across the plasma membrane by the Orai channel protein and its calcium sensor, stromal interacting molecule 1 (STIM1). STIM1 was required for increased permeability caused by thrombin; however, the role of STIM1 required neither calcium entry nor regulation of the Orai channel. Instead, STIM1 was required to activate the small guanosine triophosphatase RhoA, which coordinates remodeling of the actin cytoskeleton and reduces cell adhesion, which leads to increased permeability. Sci. Signal. 6 , ra18 (2013). [1]: pending:yes

Inhibition of AngiogenesisIn Vitroby Chebulagic Acid: A COX-LOX Dual Inhibitor

Angiogenesis is a crucial step in the growth of cancer and its metastasis. It is regulated by several endogenous factors which may stimulate or inhibit the new blood vessel growth. Besides these endogenous factors, several exogenous factors including some natural compounds are known to modulate angiogenesis. Angiogenesis being a potential target for drugs against a number of pathological conditions, search for compounds from natural sources that can affect angiogenesis is of great interest. The objective of our present study was to understand the effect of chebulagic acid, a COX-LOX dual inhibitor isolated from the fruits of Terminalia chebula Retz., on angiogenesis. The model systems used were rat aortic rings and human umbilical vein endothelial cells. The results showed that chebulagic acid exerts an antiangiogenic effect. This was evidenced from decreased sprouting in rat aortic rings and decrease in biochemical markers in endothelial cells treated with chebulagic acid. It downregulated the production of CD31, E-selectin, and vascular endothelial growth factor in human umbilical vein endothelial cells in culture (HUVEC). Further studies to understand the molecular mechanism of action of chebulagic acid revealed that CA exerts its anti angiogenic effect by modulating VE cadherin-β catenin signalling in human umbilical vein endothelial cells.

Pengaruh Likopen terhadap Penurunan Aktivitas Mitogen-Activated Protein Kinase (MAPK) dan Ekspresi Endothelin-1 (ET-1) pada Kultur Huvecs yang Dipapar Leptin

The effect of obesity on vascular function is mediated by hormon leptin. Leptin has been proved to increaseoxidative stress in endothelial cell. The previous study has proven that leptin caused the endothelial dysfunction asa step of the atherogenesis. Lycopene, an antioxidant, is presumed having the ability to block the atherogenesismechanism, which is stimulated a proinflamatory cytokine and adhesion molecules by MAPK and transcriptionfactor ET-1. Therefore, the aim of this research was to prove and to determine whether lycopene could decreasethe MAPK and ET-1 expression in Human Umbillical Vein Endothelial Cells (HUVECs) culture induced by 500 ng/mlleptin. In vitro study used primary culture of the HUVECs were devided in to 7 groups, there were (1) 0 ng/ml leptinand 0 ìM lycopene, (2) induced by 500 ng/ml leptin for 12 hours, (3) induced by leptin and lycopene with concentration10; 25; 40; 55 and 75 ìM for 12 hours. Then the identification of MAPK was applied by using imunocytochemistrycompared with ELISA procedure on cell endothel culture lysate and ET-1 expression was measured by using RTPCR. It was showed that lycopene 10-25 ìM decreased MAPK and ET-1 expression significantly in HUVECs cultureinduced by leptin 500 ng/ml. Leptin was increased ERK1/2 MAPK and ET-1 expression in HUVECs culture and candecrease by lycopene. Optimum dose of lycopene is 10-25 ìM.

Carbon monoxide-releasing molecules protect against ischemia–reperfusion injury during kidney transplantation

Carbon monoxide (CO) can provide beneficial antiapoptotic and anti-inflammatory effects in the context of ischemia-reperfusion injury (IRI). Here we tested the ability of pretreating the kidney donor with carbon monoxide-releasing molecules (CORM) to prevent IRI in a transplant model. Isogeneic Brown Norway donor rats were pretreated with CORM-2 18 h before kidney retrieval. The kidneys were then cold-preserved for 26 h and transplanted into Lewis rat recipients that had undergone bilateral nephrectomy. Allografts from Brown Norway to Lewis rats were also performed after 6 h of cold ischemic time with low-dose tacrolimus treatment. All recipients receiving CORM-2-treated isografts survived the transplant process and had near-normal serum creatinine levels, whereas all control animals died of uremia by the third post-operative day. This beneficial effect was also seen in isografted Lewis recipients receiving kidneys perfused with CORM-3, indicating that CORMs have direct effects on the kidney. Pretreatment of human umbilical vein endothelial cells in culture with CORM-2 for 1 h significantly reduced cytokine-induced nicotinamide adenine dinucleotide phosphate-dependent production of superoxide, activation of the inflammation-relevant transcription factor nuclear factor-κB, upregulated expression of E-selectin and intercellular adhesion molecule-1 adhesion proteins, and leukocyte adhesion to the endothelial cells. Thus, CORM-2-derived CO protects renal transplants from IRI by modulating inflammation.

Cardiovascular disease in recent onset diabetes mellitus

Diabetes is associated with a marked increased risk of atherosclerotic vascular disorders, including coronary, cerebrovascular, and peripheral artery disease. Cardiovascular disease (CVD) could account for disabilities and high mortality rates in patients with diabetes. Conventional risk factors, including hyperlipidemia, hypertension, smoking, obesity, lack of exercise, and a positive family history, contribute similarly to macrovascular complications in type 2 diabetic patients and non-diabetic subjects. The levels of these factors in diabetic patients are certainly increased, but not enough to explain the exaggerated risk for macrovascular complications in the diabetic population. Furthermore, recently, macrovascular complications of diabetes have been shown to start before the onset of diabetes. Indeed, several clinical studies have confirmed the increased risk of CVD in patients with impaired glucose tolerance (IGT). Since insulin resistance-related postprandial metabolic derangements are thought to play a central role in the development and progression of CVD in patients with IGT, amelioration of postprandial metabolic disturbance is a therapeutic target for the prevention of CVD in these high-risk patients. Therefore, in this paper, we review the molecular mechanisms for the increased risk of CVD in recent onset diabetes mellitus, especially focusing on postprandial dysmetabolism. We also discuss here the potential therapeutic strategies that specially target the mechanisms responsible for vascular alterations in diabetes.