Papers by Keyword: Endothelial Cell

Abstract: Vascularization is a crucial process during bone development and regeneration. A number of studies have shown that the interaction between osteoblasts and endothelial cells plays a key role in osteogenesis by using co-culture system. However, vascularization strategies in cell-based bone tissue engineering depend on optimal culture conditions. In this study, we determined the optimal co-culture conditions in view of osteogenic parameters and examined the effects of angiogenic properties on osteogenesis. As for cell proliferation, the proportion of osteoblasts increased and that of endothelial cells decreased as culture period passed. Assessment of osteogenic differentiation shows that co-culture of osteoblasts and endothelial cells significantly increased alkaline phosphatase activity and expression of bone-related genes. Furthermore, abundant microcapillary-like structures were observed which endothelial cells self-assembled into branches and net-like structures. The use of endothelial cells would be a promising strategy to promote vascularization to support the bone regeneration. Combination of these cell-based approaches and tissue engineering like three-dimensional scaffolds could provide a novel treatment therapy for bone defects and bone diseases.

Abstract: Angiogenesis is crucial for tumor progression and and migration of endothelial cells into tumor is important in the formation of new blood vessels in tumors. In this study we investigated the effect of Genistein on migration of human endothelial cells ECV-304 induced by human ovarian serous cystadenocarcinoma cell line SKOV3, and explored the mechanism of anti-angiogenesis of Genistein. Millicell chamber and coculture method were used to observe the influence on migration of ECV-304 induced by SKOV3 cells or its conditioned medium. The expression of angiogenesis associated protein VEGFbFGF and TGFβ-1 were determined using immunocytochemical assay. The results showed that either SKOV3 cells or its conditioned medium could induce the committed chemotactic migration of ECV-304. The chemotactic migrations of ECV-304 induced by SKOV3 or its conditioned medium were significantly inhibited by Genistein in a dose-dependent manner. 20μmol/L Genistein could down-regulate the expression of bFGF, and up-regulate the expression of TGFβ-1. Migrations of ECV-304 induced by SKOV3 or its conditioned medium are apparently inhibited by Genistein. It suggests that this inhibitory effect of Genistein is completed by down-regulating the expression of vessel growth-promoting factor bFGF, and up-regulating the expression of negative regulator TGFβ-1. This may be one of the mechanisms of anti-angiogenesis of Genistein.

Abstract: Hyperoside is a flavonol glycoside extraction from Hawthorn (Crataegus), and it has been reported that hyperoside process anti-inflammatory and anti-oxidative effect in vivo. In this paper, we studied the effects of hyperoside on apoptosis, necrosis, intracellular ROS level, mitochondrial transmembrane potential, and expression of Bax and Bcl-2 of endothelial cells subjected to H₂O₂,. The results showed that hyperoside treatment (50 μmol/L and 200 μmol/L ) significantly reduced apoptosis and necrosis, intracellular ROS and the expression of Bax in endothelial cell subjected to H₂O₂, and increased mitochondrial transmembrane potential and Bcl-2 expression. In conclusion, the present study indicates that hyperoside is in favor of endothelial cell protection.

Abstract: Porous Silk Fibroin Films(PSFFs) as dermis implant were used widely in biomaterials. To investigate angiogenesis in rat at different time after PSFFs implanting, CD34 was observed. Immunohistochemistry showed new blood vessels were mainly formed by sprouting next to PSFFs after 7 days operation. Microvessel Density (MVD) in PSFFs was 0, 3.54, 11.6, 24.5 after 1day, 7days, 15 days and 25days implantation respectively.

Abstract: In this paper, the Ti-O films were prepared by unbalanced magnetron sputtering deposition system. The films were then treated by plasma immersion ion implantation (PIII) using ammonia gas in order to introduce amino group to Ti-O films surface. The content of amino group on modified Ti-O films can be tested by Acid Orange II. The surface structure, roughness and the chemical composition of elements, were analyzed by x-ray diffraction(XRD),atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). After that, laminin (Ln) and fibronectin (Fn) were covalently immobilized to the surface by the amidogen. The human umbilical vein endothelial cells (HUVEC) were seeded in vitro onto the modified and unmodified Ti-O films surfaces for evaluating the cell compatibility and endothelialization trend. The morphology of endothelial cells (EC) was examined by optical microscopy.The Acid Orange II and XPS results show that the modified Ti-O films treated by plasma immersion ion implantation (PIII) contain amino groups. Endothelial cell culture experiment suggests The Laminin and Fibronectin can further enhance HUVEC adhesion and proliferation. And the PIII treated Ti-O film sample co-immobilized with Ln and Fn possess the best endothelial cell compatibility.

Abstract: Mesenchymal stem cells (MSCs) from bone marrow seem to be the one of best candidates to regenerate injured tissue. However, recent advances in application of MSCs toward large tissue regeneration are faced with lack of vascularity. In this study, endothelial cells differentiated from MSCs were applied for constructing tissue-engineered bone and cartilage. It was found that endothelial cells from MSCs play an important role of providing vasculature.

Abstract: Fibrin is a natural substrate for growth, adhesion, and migration of mature endothelial cells (ECs) and a candidate coating material in approaches to graft endothelialization. Adipose tissue represents an abundant, practical source of donor tissue for stem cells which may be a useful source for engineering of vascular grafts. However, the optimal substrates that promote differentiation of adipose tissue-derived stem cells (ASCs) into ECs remain to be elucidated. In the present study, we investigated whether fibrin can be used as a substratum to support in vitro ECs differentiation of ASCs and whether fibrinogen concentration can be affect on ECs differentiation of ASCs. For determination of phenotypic characteristics of ASCs used in this experiment, we performed flow cytometry analysis. ASCs were plated on fibrin composed of varying concentrations of fibrinogen and induced into ECs differentiation in presence of VEGF. Before inducing into ECs, ASCs did not express any markers of hematopoietic cells (CD34, CD45), ECs (CD31, CD34), and endothelial progenitor cells (CD34, CD133, Flk-1). The degree of ECs differentiation was determined by capillary network formation, ECs-specific gene expression, and F-actin assembly. During the first 12 h after seeding, cells spread randomly, moved and formed small interconnected clusters. These clusters decreased in size and formed a capillary tube at 48 h. During the further incubation in presence of VEGF for 7 days, ASCs expressed mRNA and protein of von Willebrand factor (vWF). The degree of ECs differentiation of ASCs was consistently decreased as fibrinogen concentration increase. Fibrin may be used as biomatrix to promote differentiation of ASCs into ECs for tissue engineering.

Abstract: Cerium oxide films have been fabricated using dual plasma deposition. X-ray diffraction. (XRD) reveals a crystalline phase and X-ray photoelectron spectroscopy (XPS) shows that La exists predominantly in the +4 oxidation state. The activated partial thromboplastin time is longer than that of blood plasma and stainless steel. Furthermore, the numbers of adhered, aggregated and morphologically changed platelets are reduced compared to low-temperature isotropic carbon (LTIC). HUVEC cells exhibit good adhesion and proliferation behavior on cerium oxide films. This study suggests rare earth oxide films are potential blood-contacting biomedical materials.

Abstract: A new technique for micropatterning surfaces for cell growth support is described and characterized. This technique allows covering of large three-dimensional surfaces at low cost with controllable micropatterns. This method takes advantage of the random properties of aerosols and the principles of liquid atomization. Parameters of interest were the pressure of atomization air, the flow rate and volume of the atomised liquid, and the distance between the spray nozzle and the surface of the sample. The experimental setup permitted to obtain mean diameters of spots between 10 and 20 microns with a maximum surface coverage of 20%. In an initial step, polytetrafluoroethylene (PTFE) films were treated with ammonia plasma to insert amino groups on the surface. The ammonia plasma treated films were immersed in a solution containing sulfosuccinimidyl 4-(N-maleidomethyl)cyclohexane-1-carboxy-late (SSMCC) to permit the introduction of maleimido groups on the PTFE surface to subsequently conjugate peptides through a sulfhydryl containing N-terminal cystein residue. Plasma/S-SMCC pretreated surfaces were then sprayed with peptide sequences CGRGDS and CWQPPRARI. Our data showed that spots of CGRGDS peptides over a background of CWQPPRARI peptides were the most effective combination to enhance endothelialization.