Abstract
BackgroundSialic acids represent common terminal residues on numerous mammalian glycoconjugates, thereby influencing e.g. lumen formation in developing blood vessels. Interestingly, besides monosialylated also polysialylated glycoconjugates are produced by endothelial cells. Polysialic acid (polySia) is formed in several organs during embryonal and postnatal development influencing, for instance, cell migration processes. Furthermore, the function of cytokines like basic fibroblast growth factor (bFGF) is modulated by polySia.ResultsIn this study, we demonstrated that human umbilical vein endothelial cells (HUVEC) also secrete polysialylated glycoconjugates. Furthermore, an interaction between polySia and vascular endothelial growth factor (VEGF) was observed. VEGF modulates like bFGF the migration of HUVEC. Since both growth factors interact with polySia, we examined, if polySia modulates the migration of HUVEC. To this end scratch assays were performed showing that the migration of HUVEC is stimulated, when polySia was degraded.ConclusionsSince polySia can interact with bFGF as well as VEGF and the degradation of polySia resulted in an increased cell migration capacity in the applied scratch assay, we propose that polySia may trap these growth factors influencing their biological activity. Thus, polySia might also contribute to the fine regulation of physiological processes in endothelial cells.
Highlights
Eukaryotic cells are generally covered by a glycocalyx, varying in thickness and composition and consisting of a broad range of glycoconjugates, including glycolipids, glycoproteins and proteoglycans [1]
PolySia is released by cultured human umbilical vein endothelial cells (HUVEC) PolySia is produced by endothelial cells, as already described by Naftolin and colleagues [24,25,26]
In a first set of experiments Polysialic acid (polySia) was visualized using HUVEC, which were fixed with 4% paraformaldehyde in PBS without a permeabilization step
Summary
Eukaryotic cells are generally covered by a glycocalyx, varying in thickness and composition and consisting of a broad range of glycoconjugates, including glycolipids, glycoproteins and proteoglycans [1]. While the majority of glycoconjugates contains monosialylated carbohydrate chains, some proteins are posttranslationally modified by polysialic acid (polySia) [7] These sialic acid polymers are especially present throughout the development on cells of the brain [8, 9], but are recognized in other organs like the female and male reproductive tract, where polySiapositive cells appear in a spatial–temporal manner during embryonal and postnatal development [10,11,12,13,14,15,16]. The function of cytokines like basic fibroblast growth factor (bFGF) is modulated by polySia
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
