Endothelial heparanase secretion after acute hypoinsulinemia is regulated by glucose and fatty acid

2009 ◽  
Vol 296 (4) ◽  
pp. H1108-H1116 ◽  
Author(s):  
Fang Wang ◽  
Min Suk Kim ◽  
Prasanth Puthanveetil ◽  
Girish Kewalramani ◽  
Sylvia Deppe ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Fatty Acid ◽  
Cell Surface ◽  
High Glucose ◽  
Incubation Medium ◽  
Serum Insulin ◽  
Heparan Sulphate ◽  
Cytochalasin D ◽  
Heparan Sulphate Proteoglycan ◽  
Apical Side

Following diabetes, the heart increases its lipoprotein lipase (LPL) at the coronary lumen by transferring LPL from the cardiomyocyte to the endothelial lumen. We examined how hyperglycemia controls secretion of heparanase, the enzyme that cleaves myocyte heparan sulphate proteoglycan to initiate this movement. Diazoxide (DZ) was used to decrease serum insulin and generate hyperglycemia. A modified Langendorff technique was used to separate coronary from interstitial effluent, which were assayed for heparanase and LPL. Within 30 min of DZ, interstitial heparanase increased, an effect that closely mirrored an augmentation in interstitial LPL. Endothelial cells were incubated with palmitic acid (PA) or glucose, and heparanase secretion was determined. PA increased intracellular heparanase, with no effect on secretion of this enzyme. Unlike PA, glucose dose-dependently lowered endothelial intracellular heparanase, which was strongly associated with increased heparanase activity in the incubation medium. Preincubation with cytochalasin D or nocodazole prevented the high glucose-induced depletion of intracellular heparanase. Our data suggest that following hyperglycemia, translocation of LPL from the cardiomyocyte cell surface to the apical side of endothelial cells is dependent on the ability of the fatty acid to increase endothelial intracellular heparanase followed by rapid secretion of this enzyme by glucose, which requires an intact microtubule and actin cytoskeleton.

ErbB2 Expression on Left Ventricular Epicardial Endothelial Cells and CD105+ Cells is Decreased in Patients with Diabetes Mellitus.

2021 ◽  
Author(s):  
Joanne T. deKay ◽  
Joshua Carver ◽  
Bailey Shevenell ◽  
Angela M. Kosta ◽  
Sergey Tsibulnikov ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
Endothelial Cells ◽  
Cell Surface ◽  
High Glucose ◽  
Artery Bypass ◽  
Surface Expression ◽  
Left Ventricular ◽  
Cell Surface Expression ◽  
Erbb Receptors ◽  
Diabetic Patients

Abstract Background We investigated the cell surface expression of ErbB receptors on left ventricular (LV) epicardial endothelial cells and CD105+ cells obtained from cardiac biopsies of patients undergoing coronary artery bypass grafting surgery (CABG). Methods Endothelial cells and CD105+ non-endothelial cells were freshly isolated from LV epicardial biopsies obtained from 15 subjects with diabetes mellitus (DM) and 8 controls. The expression of ErbB recepotrs was examined using multiparametric flow cytometry. Human microvascular endothelial cells (HMEC-1) and LV epicardial CD105+ non-endothelial cells were used to determine the effect of high glucose on ADAM10-dependent cleavage of ErbB receptors. Results We found that diabetes mellitus (DM) and high levels of hemoglobin A1C are associated with reduced expression of ErbB2 on both endothelial cells and CD105+ non-endothelial cells. To determine if the expression of ErbB2 receptors is regulated by glucose levels, we examined the effect of high glucose in HMEC-1 and LV epicardial CD105+ non-endothelial cells, using a novel flow cytometric approach to simultaneously determine the total level, cell surface expression, and phosphorylation of ErbB2. Incubation of cells in the presence of 25 mM D-glucose resulted in decreased cell surface expression of ErbB2. We also found high expression of a disintegrin and metalloproteinase domain-containing protein 10 (ADAM10) on both endothelial cells and CD105+ non-endothelial cells. Inhibition of ADAM10 prevented the high glucose-dependent decrease in the cell surface expression of ErbB2. Conclusions We suggest that high glucose depresses ErbB receptor signaling in endothelial cells and cardiac progenitor cells via the promotion of ADAM10-dependent cleavage of ErbB2 at the cell surface, thus contributing to vascular dysfunction and adverse remodeling seen in diabetic patients.

scholarly journals Degradation of Sulphated Glycosaminoglycans at the Surface of Cultured Human Endothelial Cells by a Platelet Heparitinase

1977 ◽  
Author(s):  
C. Busch ◽  
B. Glimelius ◽  
Å Wastesson ◽  
B. Westermark
Keyword(s):  
Endothelial Cells ◽  
Cell Surface ◽  
Incubation Medium ◽  
Chondroitin Sulphate ◽  
Coagulation Factors ◽  
Platelet Lysate ◽  
Human Endothelial Cells ◽  
Endothelial Cell Surface ◽  
Sulphated Glycosaminoglycans

The non-thrombogenic property of the endothelial cell surface is a prerequisite for maintainance of blood circulation. The nature of this property is poorly understood. Recent advances in culturing techniques of endothelial cells in vitro may facilitate studies of the surface biochemistry. Human endothelial cells (EC) isolated from umbilical veins were shown to synthesize and secrete sulphated glycosaminoglycans (GAG). The recent finding of a platelet enzyme capable of degrading heparin sulphate (HS) raised the question:Can platelet lysate or a purified heparitinase detach and degrade endothelial HS? EC cultured in the presence of 35S-sulphate, produce 35S-labelled GAG which was isolated from the incubation medium from a cell associated trypsin labile pool and from a cellular pool not liberated by trypsin. After 48 hours of incorporation about 95% of 35S-GAG was found in the medium fraction, 5% in the trypsin fraction and negligible amounts in the cell fraction. In the trypsin pool (“surface fraction”) heparin sulphate comprised about 85%, while the remaining 15% consisted of chondroitin sulphate and/or dermatan sulphate. Incubation of 35S-labelled EC with platelet lysate or a partially purified preparation of the enzyme from the same source caused a marked release of cell-surface associated HS to the incubation medium as oligosaccharides. These effects could be ascribed to heparitinase activity and may alter the properties of the EC-surface and influence the interaction between these cells on one hand and blood cells or plasma components, e.g., coagulation factors on the other.

Identification of CD146 as a component of the endothelial junction involved in the control of cell-cell cohesion

Blood ◽  
2001 ◽  
Vol 98 (13) ◽  
pp. 3677-3684 ◽  
Author(s):  
Nathalie Bardin ◽  
Francine Anfosso ◽  
Jean-Marc Massé ◽  
Elisabeth Cramer ◽  
Florence Sabatier ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Cell Surface ◽  
Umbilical Vein ◽  
Cell Surface Expression ◽  
Cell Junction ◽  
Immunoglobulin Superfamily ◽  
Cell Surface Molecule ◽  
Apical Side ◽  
Endothelial Junction ◽  
Cell Cell

Abstract CD146 is a cell-surface molecule belonging to the immunoglobulin superfamily and expressed in all types of human endothelial cells. Confocal and electron microscopic analysis of confluent human umbilical vein endothelial cells (HUVECs) were used to demonstrate that CD146 is a component of the endothelial junction. Double immunolabeling with vascular endothelial cadherin showed that CD146 is localized outside the adherens junction. Moreover, CD146 expression is not restricted to the junction, since part of the labeling was detectable at the apical side of the HUVECs. Interestingly, cell-surface expression of CD146 increased when HUVECs reached confluence. In addition, the paracellular permeability of CD146-transfected fibroblast cells was decreased compared with that of control cells. Finally, CD146 colocalized with actin, was partly resistant to Triton X-100 extraction, and had its expression altered by actin-disrupting agents, indicating that CD146 is associated with the actin cytoskeleton. These results show the regulated expression of CD146 at areas of cell-cell junction and strongly suggest involvement of CD146 as a mediator of cell-cell interaction.

scholarly journals Identification of the core proteins in proteoglycans synthesized by vascular endothelial cells

1989 ◽  
Vol 261 (1) ◽  
pp. 145-153 ◽  
Author(s):  
A Lindblom ◽  
I Carlstedt ◽  
L Å Fransson
Keyword(s):  
Endothelial Cells ◽  
Molecular Mass ◽  
Core Protein ◽  
Heparan Sulphate ◽  
Buoyant Density ◽  
Cell Extract ◽  
Apparent Molecular Mass ◽  
Heparan Sulphate Proteoglycan ◽  
Sulphate Proteoglycan ◽  
Core Proteins

Proteoglycans, metabolically labelled with [3H]leucine and 35SO4(2-), were isolated from the spent media and from guanidinium chloride extracts of cultured human umbilical-vein endothelial cells by using isopycnic density-gradient centrifugation, gel filtration and ion-exchange h.p.l.c. The major proteoglycan species were subjected to SDS/polyacrylamide-gel electrophoresis before and after enzymic degradation of the polysaccharide chains. The cell extract contained mainly a heparan sulphate proteoglycan that has a buoyant density of 1.31 g/ml and a protein core with apparent molecular mass 300 kDa. The latter was heterogeneous and migrated as one major and one minor band. After reduction, the apparent molecular mass of the major band increased to approx. 350 kDa, indicating the presence of intrachain disulphide bonds. The proteoglycan binds to octyl-Sepharose and its polysaccharide chains are extensively degraded by heparan sulphate lyase. The proteoglycans of the medium contained 90% of all the incorporated 35SO4(2-). Here the predominant heparan sulphate proteoglycan was similar to that of the cell extract, but was more heterogeneous and contained an additional core protein with apparent molecular mass 210 kDa. Furthermore, two different chondroitin sulphate proteoglycans were found: one 200 kDa species with a high buoyant density (approx. 1.45 g/ml) and one 100 kDa species with low buoyant density (approx. 1.3 g/ml). Both these proteoglycans have a core protein of molecular mass approx. 47 kDa.

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