Clinical Hemorheology and Microcirculation - Volume 37, issue 1-2

Authors: Stolz, J.F.

Article Type: Other

Citation: Clinical Hemorheology and Microcirculation, vol. 37, no. 1-2, pp. 1-1, 2007

Authors: Stoltz, J.F. | Muller, S. | Kadi, A. | Decot, V. | Menu, P. | Bensoussan, D.

Article Type: Research Article

Abstract: Vascular endothelial cells form a monocellular layer on blood vessel walls with an estimated mass of 1.5 kg. One of the roles of endothelial cells is to control the hemodynamics through various metabolic activities affecting homeostasis, vascular tonus, blood fluidity, coagulating properties and blood cell adhesion. In other respects thousands of studies have underlined the crucial role of local blood flow conditions on their properties. However, the hemodynamic forces are different according to the anatomical site and to the type of blood vessels (arteries, veins, venules, ...). In microcirculation, the endothelial cells in the venules are particularly active and constitute …the physiological site of liquid exchange (permeability) and above all cellular transit. During critical ischemia, the post-capillary venules are deeply involved. In other respects the properties of endothelial cells may be impaired in many diseases as atherosclerosis, hypertension, inflammation and metabolic diseases. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 37, no. 1-2, pp. 5-8, 2007

Authors: Born, Gustav V.R. | Medina, R. | Shafi, S. | Cardona-Sanclemente, L.E.

Article Type: Research Article

Citation: Clinical Hemorheology and Microcirculation, vol. 37, no. 1-2, pp. 9-18, 2007

Authors: Antonova, G. | Lichtenbeld, H. | Xia, T. | Chatterjee, A. | Dimitropoulou, C. | Catravas, J.D.

Article Type: Research Article

Abstract: Although the existence of hsp90–NOS and hsp90–sGC complexes is now firmly established, their role in many pathophysiological processes remain unclear. These complexes may represent physiological mechanisms aimed at maximizing intracellular cGMP production in response to endogenous or drug-derived NO in endothelial cells and thus affecting permeability, proliferation, migration and apoptosis. Along with minimizing NO scavenging by superoxide and reducing the formation of peroxynitrite, these complexes may also prolong sGC stability by retarding its degradation. Our work and that of others have demonstrated that, depending on the environment, sGC interaction with hsp90 can optimize sGC enzyme activity or modulate sGC survival. …This review addresses the functional significance of hsp90 complexes with NOS (eNOS, iNOS) and sGC in endothelial cells relevant for maintaining endothelial barrier integrity and angiogenesis. Structural and functional characteristics of sGC, its expression, transcriptional and post-translational regulation, as they relate to sGC–hsp90 interactions, will also be examined. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 37, no. 1-2, pp. 19-35, 2007

Authors: Ohashi, Toshiro | Masuda, Masanori | Matsumoto, Takeo | Sato, Masaaki

Article Type: Research Article

Abstract: We have developed a novel uniaxial cyclic stretching technique to apply a ventral nonuniform strain to cells. In this system cells are grown on a glass-embedded silicone substrate instead of the commonly used uniform substrates. This unique substrate has been developed to give a strain gradient of 0.2%/μm across each individual cell. Bovine aortic endothelial cells (BAECs) were cyclically stretched up to a maximum strain of 50% at 0.5 Hz for 30 min or 3 hours, focusing on the effect of the ventral strain gradient on local cell remodeling. After the experiments, BAECs were fixed and stained with rhodamine-phalloidin to …observe actin filament structure. BAECs showed local development of stress fibers and localization of cell nuclei at regions exposed to higher strain. This result suggests that BAECs may sense ventral nonuniform strain and remodel cytoskeletal structure accordingly followed by the movement of cell nuclei. Show more

Keywords: Endothelial cells, nonuniform strain, uniaxial cyclic stretching, remodeling, stress fibers, nuclei

Citation: Clinical Hemorheology and Microcirculation, vol. 37, no. 1-2, pp. 37-46, 2007

Authors: Lehoux, Stephanie

Article Type: Research Article

Citation: Clinical Hemorheology and Microcirculation, vol. 37, no. 1-2, pp. 47-55, 2007

Authors: Schweighofer, Bernhard | Schultes, Julia | Pomyje, Jiří | Hofer, Erhard

Article Type: Research Article

Abstract: The evaluation of signaling pathways leading to gene induction by VEGF-A and IL-1 in endothelial cells supports the importance of the NF-κB pathway for the IL-1-induced gene repertoire, whereas VEGF-A is a strong and preferential trigger of signals via PLC-γ. This leads (i) via Ca++ to the activation of calcineurin and NFAT and (ii) via PKC and the MEK/ERK MAPK pathway to the upregulation of EGR-1. Part of the VEGF-triggered gene induction depends on a cooperation of the transcription factors NFAT and EGR-1. Gene activation via PLC-γ provides VEGF with the potency to induce a wide spectrum of genes …including many also upregulated by IL-1. A gene upregulated by VEGF and IL-1 is the DSCR-1 gene, which encodes an inhibitor of calcineurin. DSCR1 is induced by NFAT or NF-κB and limits Ca++ signaling in a negative feed-back loop. Similarly, NAB2, a corepressor of EGR-1, is induced by EGR-1 and limits EGR-1 effects. Adenoviral overexpression of DSCR1 or NAB2 inhibited part of VEGF-induced gene expression and reduced sprouting in angiogenesis models. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 37, no. 1-2, pp. 57-62, 2007

Authors: Kwan, H.Y. | Huang, Y. | Yao, X.

Article Type: Research Article

Abstract: Ca2+ mobilizing agonists and hemodynamic shear stress both elicit a rise in endothelial cytosolic Ca2+ [Ca2+ ]i , which then acts to stimulate nitric oxide synthase and phospholipase A2 , leading to the production and release of nitric oxide (NO) and other vascular substances such as prostacyclin and endothelium-derived hyperpolarizing factors (EDHF). In this article, regulatory mechanisms of agonist-induced and mechanosensitive Ca2+ influx pathways in vascular endothelial cells will be discussed. Special emphasis will be placed on the regulation of agonist-induced Ca2+ influx by protein kinase G (PKG). Flow-induced Ca2+ influx in relation to vascular …dilation and the vasodilator produced will also be discussed. Show more

Citation: Clinical Hemorheology and Microcirculation, vol. 37, no. 1-2, pp. 63-70, 2007

Authors: Kakou, Augustine | Louis, Huguette | Cattan, Valérie | Lacolley, Patrick | Thornton, Simon N.

Article Type: Research Article

Abstract: This review presents some of the recent technological developments in biomaterials used for the construction of synthetic cardiovascular vessels that are capable of simulating specific biological responses. However, with respect to the problems of stiffness, a major hypertensive risk factor, it is necessary to underline the important role of mechanical properties, such as vessel strength and composition, in vascular reconstructive surgery. Biomaterials occupy a central place in many cardiovascular disease treatments and they depend on the chemical nature of the polymers, on the biotechnology used, and also on cellular and gene therapy. Several methodologies using animal or human cells have …emerged for constructing blood vessel replacements. Tissue-engineered blood vessel (TEBV) substitutes begin to motivate much work and have contributed to the restoration, maintenance, and/or improvement in tissue and organ function. Each methodology has it benefits, its promises, and holds many challenges in future biological, biomaterial and clinical research. Show more

Keywords: Cardiovascular, tissue engineering, vascular graft, biomaterial, mechanical strength

Citation: Clinical Hemorheology and Microcirculation, vol. 37, no. 1-2, pp. 71-75, 2007

Authors: Werkmeister, E. | Kerdjoudj, H. | Marchal, L. | Stoltz, J.F. | Dumas, D.

Article Type: Research Article

Abstract: Imaging thick and opaque tissue, like blood vessel, in a noninvasive mode with high resolution, is nowadays possible with multiphoton technology. A near-infrared excitation presents the advantage to be compatible with living specimens and allows a deep penetration into tissues. The nonlinear excitation process is followed by several deactivation ways, among which fluorescence emission can be represented with Spectral or Lifetime imaging. Applied to ex vivo blood vessel imaging, these techniques enabled us to discriminate cell structures (nucleus, cytoskeleton) by fluorescent labelling (Hoechst, QDots). Another method, based on 2-photon excitation and which doesn't need any exogenous dye has also been …experimented on arteries: SHG (Second Harmonic Generation) is a diffusion process generated from organized structures. Collagen molecules give rise to a strong SHG signal, enabling us to image the arterial wall (3-dimensional extracellular matrix). Show more

Keywords: Spectral imaging, fluorescence lifetime imaging microscopy, second harmonic generation

Citation: Clinical Hemorheology and Microcirculation, vol. 37, no. 1-2, pp. 77-88, 2007