Human Dermal Microvascular Endothelial Cells (human + dermal_microvascular_endothelial_cell)

Distribution by Scientific Domains


Selected Abstracts


Mapping pro- and antiangiogenic factors on the surface of prostasomes of normal and malignant cell origin

THE PROSTATE, Issue 8 2010
Adil A. Babiker
Abstract BACKGROUND Angiogenesis is the formation of new blood vessels by capillary sprouting from pre-existing vessels. Tumor growth is angiogenesis-dependent and the formation of new blood vessels is associated with the increased expression of angiogenic factors. Prostasomes are secretory granules produced, stored and released by the glandular epithelial cells of the prostate. We investigated the expression of selected angiogenic and anti-angiogenic factors on the surface of prostasomes of different origins as well as the direct effect of prostasomes on angiogenesis. METHODS VEGF, endothelin-1, endostatin, and thrombospondin-1 were determined on prostasomes from seminal fluid and human prostate cancer cell lines (DU145,PC-3,LNCaP) using different immunochemical techniques. Human dermal microvascular endothelial cells were incubated with seminal and DU145 cell-prostasomes and with radioactive thymidine. The effect of prostasomes on angiogenesis was judged by measuring the uptake of labeled thymidine. The presence of any deleterious effects of prostasomes on the endothelial cells was investigated using thymidine assay and confocal laser microscopy. RESULTS VEGF and endothelin-1 were determined on malignant cell-prostasomes (no difference between cell lines) but not determined on seminal prostasomes. The same applies for the expression of endostatin but with much higher expression on malignant cell-prostasomes with obvious differences between them. Seminal and DU145 cell-prostasomes were found to have anti-angiogenic effect which was more expressed by DU145 cell-prostasomes. No deleterious effect of prostasomes on endothelial function was detected using either thymidine assay or microscopy. CONCLUSIONS Prostasomes contain pro- and anti-angiogenic factors that function to counteract each other unless the impact from one side exceeds the other to bring about dysequilibrium. Prostate 70: 834,847, 2010. © 2010 Wiley-Liss, Inc. [source]


Sonic hedgehog derived from human pancreatic cancer cells augments angiogenic function of endothelial progenitor cells

CANCER SCIENCE, Issue 6 2008
Madoka Yamazaki
Hedgehog signaling is important in the pathogenesis of pancreatic cancer. Several recent observations suggest the involvement of sonic hedgehog (SHH) in postnatal neovascularization. We identified a novel role for SHH in tumor-associated angiogenesis in pancreatic cancer. Immunohistochemical analysis revealed that patched homolog 1 (PTCH1), both a receptor for and transcriptional target of hedgehog signaling, was expressed in a small fraction of endothelial cells within pancreatic cancer, but not in normal pancreatic tissue. When endothelial progenitor cells (EPC) isolated from human peripheral blood were cultured with supernatant from SHH-transfected 293 cells or pancreatic cancer cells, mRNA levels of vascular endothelial growth factor (VEGF), stromal cell-derived factor-1 and angiopoietin-1 were significantly increased, whereas no such induction was observed in human umbilical vein endothelial cell (HUVEC) and human dermal microvascular endothelial cell (HMVEC). HUVEC tube formation was stimulated when cocultured with EPC, and preconditioning EPC with supernatant from KP-1 N pancreatic cancer cells highly expressing SHH significantly enhanced the effect. The effect was partially attenuated by specific inhibition of SHH with cyclopamine or a neutralizing antibody. These findings suggest that tumor-derived SHH can induce angiogenesis, and this is mediated by its effects on EPC specifically. Targeting SHH would be a novel therapeutic approach that can inhibit not only proliferation of cancer cells but also EPC-mediated angiogenesis. (Cancer Sci 2008; 99: 1131,1138) [source]


Expression of psoriasis-associated fatty acid-binding protein in senescent human dermal microvascular endothelial cells

EXPERIMENTAL DERMATOLOGY, Issue 9 2004
Moon Kyung Ha
Abstract:, Aging is associated with the progressive pathophysiologic modification of endothelial cells. In vitro endothelial cell senescence is accompanied by proliferative activity failure and by perturbations in gene and protein expressions. Moreover, this cellular senescence in culture has been proposed to reflect processes that occur in aging organisms. In order to observe the changing patterns of protein expression in senescent human dermal microvascular endothelial cells (HDMECs), proteins obtained from both early- and late-passaged HDMECs were separated by two-dimensional electrophoresis, visualized by silver staining, and quantified by image processing. Proteins of interest were extracted by in-gel digestion with trypsin and quantified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), by searching the National Center for Biotechnology Information protein-sequence database. More than 2000 spots were detected by 2D electrophoresis within a linear pH range of 3,10. Twenty-two major differentially expressed spots were observed in serially passaged HDMECs and identified with high confidence by MALDI-TOF-MS. One of these spots was found to be a 14,15 kDa psoriasis-associated fatty acid-binding protein (PA-FABP) with high affinity for long-chain fatty acids. The expression of PA-FABP was confirmed to be elevated in senescent HDMECs (passage 20) by fluorescence-activated cell sorting (FACS), confocal laser microscopy, and by immunohistochemistry in aged human skin tissue. Our results suggest that the overexpression of FABP in cultured senescent HDMECs is closely related to skin aging. [source]


An in vitro examination of an extracellular matrix scaffold for use in wound healing

INTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 5 2002
Denis E. Solomon
Summary. This paper describes evidence that an extracellular matrix (ECM) secreted by human umbilical vein endothelial cells (HUVECs) assembled on gelatin coated plates overlaid by a mixed matrix secreted by human dermal microvascular endothelial cells (HDMECs) and human dermal fibroblasts provides a viable acellular scaffold for use in wound healing. Trypsinized epidermal keratinocytes or colonies from Dispase-digested fresh and cadaver skin tissue adhered and proliferated on either HUVECs ECM/gelatin or mixed matrix overlaid on HUVECs ECM/gelatin. An epithelial,mesenchymal interaction, previously thought to be tissue-specific, was exposed as well as concomitant integrin versatility. Furthermore, heterologous HDMECs and dermal fibroblasts attached and proliferated on the mixed matrix as well as HUVECs ECM. The conditioned medium from HUVECs (HUVECs CM) was found to neutralize the lingering after effects of Dispase, and could be used for the tissue culture of epidermal keratinocytes, HDMECs and dermal fibroblasts, which share related extracellular secretions. Taken together, these results indicate that cultured epithelial autografts can be redesigned to include both epithelial and dermal elements, and advances the acellular ,sandwich' ECM scaffold as a possible structural replacement for the lamina densa and lamina lucida, damaged or completely missing in some wounds and burns. [source]


Role of Rac 1 and cAMP in endothelial barrier stabilization and thrombin-induced barrier breakdown

JOURNAL OF CELLULAR PHYSIOLOGY, Issue 3 2009
Y. Baumer
Barrier stabilizing effects of cAMP as well as of the small GTPase Rac 1 are well established. Moreover, it is generally believed that permeability-increasing mediators such as thrombin disrupt endothelial barrier functions primarily via activation of Rho A. In this study, we provide evidence that decrease of both cAMP levels and of Rac 1 activity contribute to thrombin-mediated barrier breakdown. Treatment of human dermal microvascular endothelial cells (HDMEC) with Rac 1-inhibitor NSC-23766 decreased transendothelial electrical resistance (TER) and caused intercellular gap formation. These effects were reversed by addition of forskolin/rolipram (F/R) to increase intracellular cAMP but not by the cAMP analogue 8-pCPT-2,-O-Methyl-cAMP (O-Me-cAMP) which primarily stimulates protein kinase A (PKA)-independent signaling via Epac/Rap 1. However, both F/R and O-Me-cAMP did not increase TER above control levels in the presence of NSC-23766 in contrast to experiments without Rac 1 inhibition. Because Rac 1 was required for maintenance of barrier functions as well as for cAMP-mediated barrier stabilization, we tested the role of Rac 1 and cAMP in thrombin-induced barrier breakdown. Thrombin-induced drop of TER and intercellular gap formation were paralleled by a rapid decrease of cAMP as revealed by fluorescence resonance energy transfer (FRET). The efficacy of F/R or O-Me-cAMP to block barrier-destabilizing effects of thrombin was comparable to Y27632-induced inhibition of Rho kinase but was blunted when Rac 1 was inactivated by NSC-23766. Taken together, these data indicate that decrease of cAMP and Rac 1 activity may be an important step in inflammatory barrier disruption. J. Cell. Physiol. 220: 716,726, 2009. © 2009 Wiley-Liss, Inc. [source]


Inflammatory cytokines induce the transformation of human dermal microvascular endothelial cells into myofibroblasts: a potential role in skin fibrogenesis

JOURNAL OF CUTANEOUS PATHOLOGY, Issue 2 2007
V. Chaudhuri
Background:, The myofibroblast plays a central role in wound contraction and in the pathology of fibrosis. The origin(s) of this important cell type in skin has not been firmly established. Methods:, Human epithelioid dermal microvascular endothelial cells (HDMEC) were isolated from foreskin tissue and maintained in cell culture. The transformation of epithelioid HDMEC into myofibroblasts (EMT) was induced by the inflammatory cytokines interleukin-1, (IL-1,) or tumour necrosis factor-, (TNF-,), and the transformed cells were characterized by electron microscopy, immunohistochemistry and quantitative RT-PCR. Results:, After short-term exposure to IL-1, or TNF-, (<3 days), EMT was reversible; after long-term exposure (>10 days), EMT was permanent. The transformed cells were identified as myofibroblasts by cytoplasmic microfilaments with dense bodies and attachment plaques, by the expression of ,-smooth muscle actin, type I collagen and calponin, and by quantitative RT-PCR gene expression of type I collagen and ,-smooth muscle actin. Conclusions:, Long-term exposure to TNF-, or IL-1, induced the permanent transformation of HDMEC into myofibroblasts in cell culture. A similar transformation following chronic inflammatory stimulation in vivo may explain one source of myofibroblasts in skin fibrogenesis. [source]