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Endothelial Cell Growth (endothelial + cell_growth)
Terms modified by Endothelial Cell Growth Selected AbstractsDesign of Fibrin Matrix Composition to Enhance Endothelial Cell Growth and Extracellular Matrix Deposition for In Vitro Tissue EngineeringARTIFICIAL ORGANS, Issue 1 2009Divya Pankajakshan Abstract Tissue-engineered blood vessel substitutes should closely resemble native vessels in terms of structure, composition, mechanical properties, and function. Successful cardiovascular tissue engineering requires optimization of in vitro culture environment that would produce functional constructs. The extracellular matrix (ECM) protein elastin plays an essential role in the cardiovascular system to render elasticity to blood vessel wall, whereas collagen is responsible for providing mechanical strength. The objective of this study was to understand the significance of various ECM components on endothelial cell (EC) growth and tissue generation. We demonstrate that, even though fibrin is a good matrix for EC growth, fibronectin is the crucial component of the fibrin matrix that enhances EC adhesion, spreading, and proliferation. Vascular EC growth factor is known to influence in vitro growth of EC, but, so far, ECM deposition in in vitro culture has not been reported. In this study, it is shown that incorporation of a mixture of hypothalamus-derived angiogenic growth factors with fibrin matrix enhances synthesis and deposition of insoluble elastin and collagen in the matrix, within 10 days of in vitro culture. The results suggest that a carefully engineered fibrin composite matrix may support EC growth, survival, and remodeling of ECM in vitro and impart optimum properties to the construct for resisting the shear stress at the time of implantation. [source] Endothelial cell growth on silicon modified hydrogenated amorphous carbon thin filmsJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2008A. A. Ogwu Abstract The biological response of human microvascular endothelial cells (HMEC-1) seeded on Si-DLC films and on control surfaces was evaluated in terms of initial cell enhancement, growth, and cytotoxicity. The microstructure of the films was characterised by Raman spectroscopy and X-ray photoelectron spectroscopy. The effect of changes in microstructure, surface energy, surface electronic state, and electronic conduction, on the biological response of the films to endothelial cells was investigated. Endothelial cell adhesion and growth was found to be affected by changes in the microstructure of the films induced by silicon doping and thermal annealing. We observed a significant statistical difference in endothelial cell count between the as-deposited DLC and Si-DLC films using the one sample t -test at a p -value of 0.05. We also found a statistically significant difference between the adhesion of HMEC films on DLC and Si-DLC films at various annealing temperatures using the one-way ANOVA F statistic test at p < 0.05 and the post-hoc Tukey test. One sample t -test at p < 0.05 of MTT-assay results showed the endothelial cells to be viable when seeded on DLC/Si-DLC films. We suspect that the increased adhesion of endothelial cells induced by increasing the amount of silicon in the Si-DLC films is associated with the development of a suitable surface energy due to silicon addition, which neither favored cell denaturing nor preferential water spreading before cellular attachment on the film surface. The presence of an external positively charged dipole on the Si-DLC films confirmed by our Kelvin probe measurements is also expected to enhance the adhesion of endothelial cells that are well known to carry a negative charge. The Si-DLC films investigated hold potential promise as coatings for haemocompatible artificial implants. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008 [source] Endothelial cell-derived bone morphogenetic proteins regulate glial differentiation of cortical progenitorsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 7 2008Tetsuya Imura Abstract Gliogenesis is an important component of cortical development during the postnatal period. Two macroglial cells are generated in a particular order, i.e. astrocytes first and oligodendrocytes later. The mechanisms underlying this sequence of glial differentiation are unknown but interactions with blood vessels are postulated to play a role. We show, using a mouse in-vitro coculture system, that endothelial cells promote astrocyte differentiation but inhibit oligodendrocyte differentiation of postnatal cortical progenitors. Endothelial cells produce bone morphogenetic proteins (BMPs) to activate Sma- and Mad-related protein (Smad) signalling in progenitors and the effects of endothelial cells on glial differentiation are blocked by the BMP antagonist Noggin. Differentiation of progenitors into astrocytes results in the inhibition of endothelial cell growth, accompanied by changes in gene expression of angiogenic factors, indicating bidirectional interactions between progenitors and endothelial cells. In vivo, Smad signalling is activated in various types of cortical cells including progenitors in association with astrogenesis but is inactivated before the peak of oligodendrogenesis. Capillary vessels isolated from the developing cortex express high levels of BMPs. Together, these results demonstrate that endothelial cells regulate glial differentiation by secreting BMPs in vitro and suggest a similar role in cortical gliogenesis in vivo. [source] FGF-2 but not FGF-1 binds fibrin and supports prolonged endothelial cell growthJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 6 2003A. Sahni Summary., Endothelial cell viability and growth are dependent on both polypeptide growth factors, and integrin-mediated matrix interactions. We have now examined the ability of fibrin-binding and non-binding growth factors to support long-term endothelial cell growth in the presence or absence of the soluble form. Endothelial cells were cultured on a fibrin surface, with or without FGF-1 or FGF-2, and proliferation was determined by 3H-thymidine incorporation. Cells cultured on fibrin with no growth factor showed minimal proliferation up to 96 h. In contrast, when FGF-2 was incorporated into fibrin, proliferation was increased 6.5 ± 0.6-fold, equal to growth on a fibrin surface with FGF-2 continually present in the medium. Thymidine incorporation was similar when cells were cultured on a fibrin surface that had been incubated with FGF-2 and then the growth factor removed (8.6 ± 0.5-fold). In contrast to results with FGF-2, a surface of fibrin exposed to FGF-1 supported minimal growth, whereas growth was comparable to either FGF-1 or FGF-2 present in the medium. Comparable results were observed when proliferation was quantitated by cell counting at times up to 48 h. Binding studies demonstrated no high-affinity interaction of FGF-1 with fibrinogen or fibrin. We conclude that FGF-2 bound to fibrin supports prolonged endothelial cell growth as well as soluble FGF-2, whereas FGF-1 does not bind to fibrin and can support endothelial cell growth only if continually present in soluble form. Fibrin may serve as a matrix reservoir for FGF-2 to support cell growth at sites of injury or thrombosis. [source] The dual role of thymidine phosphorylase in cancer development and chemotherapyMEDICINAL RESEARCH REVIEWS, Issue 6 2009Annelies Bronckaers Abstract Thymidine phosphorylase (TP), also known as "platelet-derived endothelial cell growth factor" (PD-ECGF), is an enzyme, which is upregulated in a wide variety of solid tumors including breast and colorectal cancers. TP promotes tumor growth and metastasis by preventing apoptosis and inducing angiogenesis. Elevated levels of TP are associated with tumor aggressiveness and poor prognosis. Therefore, TP inhibitors are synthesized in an attempt to prevent tumor angiogenesis and metastasis. TP is also indispensable for the activation of the extensively used 5-fluorouracil prodrug capecitabine, which is clinically used for the treatment of colon and breast cancer. Clinical trials that combine capecitabine with TP-inducing therapies (such as taxanes or radiotherapy) suggest that increasing TP expression is an adequate strategy to enhance the antitumoral efficacy of capecitabine. Thus, TP plays a dual role in cancer development and therapy: on the one hand, TP inhibitors can abrogate the tumorigenic and metastatic properties of TP; on the other, TP activity is necessary for the activation of several chemotherapeutic drugs. This duality illustrates the complexity of the role of TP in tumor progression and in the clinical response to fluoropyrimidine-based chemotherapy. © 2009 Wiley Periodicals, Inc. Med Res Rev, 29, No. 6, 903,953, 2009 [source] Effects of weak static magnetic fields on endothelial cellsBIOELECTROMAGNETICS, Issue 4 2010Carlos F. Martino Abstract Pulsed electromagnetic fields (PEMFs) have been used extensively in bone fracture repairs and wound healing. It is accepted that the induced electric field is the dose metric. The mechanisms of interaction between weak magnetic fields and biological systems present more ambiguity than that of PEMFs since weak electric currents induced by PEMFs are believed to mediate the healing process, which are absent in magnetic fields. The present study examines the response of human umbilical vein endothelial cells to weak static magnetic fields. We investigated proliferation, viability, and the expression of functional parameters such as eNOS, NO, and also gene expression of VEGF under the influence of different doses of weak magnetic fields. Applications of weak magnetic fields in tissue engineering are also discussed. Static magnetic fields may open new venues of research in the field of vascular therapies by promoting endothelial cell growth and by enhancing the healing response of the endothelium. Bioelectromagnetics 31:296,301, 2010. © 2010 Wiley-Liss, Inc. [source] Functional and structural properties of stannin: Roles in cellular growth, selective toxicity, and mitochondrial responses to injuryJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 2 2006M.L. Billingsley Abstract Stannin (Snn) was discovered using subtractive hybridization methodology designed to find gene products related to selective organotin toxicity and apoptosis. The cDNAs for Snn were first isolated from brain tissues sensitive to trimethyltin, and were subsequently used to localize, characterize, and identify genomic DNA, and other gene products of Snn. Snn is a highly conserved, 88 amino acid protein found primarily in vertebrates. There is a minor divergence in the C-terminal sequence between amphibians and primates, but a nearly complete conservation of the first 60 residues in all vertebrates sequenced to date. Snn is a membrane-bound protein and is localized, in part, to the mitochondria and other vesicular organelles, suggesting that both localization and conservation are significant for the overall function of the protein. The structure of Snn in a micellar environment and its architecture in lipid bilayers have been determined using a combination of solution and solid-state NMR, respectively. Snn structure comprised a single transmembrane domain (residues 10,33), a 28-residue linker region from residues 34,60 that contains a conserved CXC metal binding motif and a putative 14-3-3, binding region, and a cytoplasmic helix (residues 61,79), which is partially embedded into the membrane. Of primary interest is understanding how this highly-conserved peptide with an interesting structure and cellular localization transmits both normal and potentially toxic signals within the cell. Evidence to date suggests that organotins such as trimethyltin interact with the CXC region of Snn, which is vicinal to the putative 14-3-3 binding site. In vitro transfection analyses and microarray experiments have inferred a possible role of Snn in several key signaling systems, including activation of the p38-ERK cascade, p53-dependent pathways, and 14-3-3, protein-mediated processes. TNF, can induce Snn mRNA expression in endothelial cells in a PKC-, dependent manner. Studies with Snn siRNA suggest that this protein may be involved in growth regulation, since inhibition of Snn expression alone leads to reduced endothelial cells growth and induction of COP-1, a negative regulator of p53 function. A key piece of the puzzle, however, is how and why such a highly-conserved protein, localized to mitochondria, interacts with other regulatory proteins to alter growth and apoptosis. By knowing the structure, location, and possible signaling pathways involved, we propose that Snn constitutes an important sensor of mitochondrial damage, and plays a key role in the mediation of cross-talk between mitochondrial and nuclear compartments in specific cell types. J. Cell. Biochem. 98: 243,250, 2006. © 2006 Wiley-Liss, Inc. [source] | |||||||||||||