title: Viscoelastic response of a model endothelial glycocalyx.
abstract: Many cells cover themselves with a multifunctional polymer coat, the pericellular matrix (PCM), to mediate mechanical interactions with the environment. A particular PCM, the endothelial glycocalyx (EG), is formed by vascular endothelial cells at their luminal side, forming a mechanical interface between the flowing blood and the endothelial cell layer. The glycosaminoglycan (GAG) hyaluronan (HA) is involved in the main functions of the EG, mechanotransduction of fluid shear stress and molecular sieving. HA, due to its length, is the only GAG in the EG or any other PCM able to form an entangled network. The mechanical functions of the EG are, however, impaired when any one of its components is removed. We here used microrheology to measure the effect of the EG constituents heparan sulfate, chondroitin sulfate, whole blood plasma and albumin on the high-bandwidth mechanical properties of a HA solution. Furthermore, we probed the effect of the hyaldherin aggrecan, a constituent of the PCM of chondrocytes, and very similar to versican (present in the PCM of various cells, and possibly in the EG). We show that components directly interacting with HA (chondroitin sulfate and aggrecan) can increase the viscoelastic shear modulus of the polymer composite.
authors: Department of Biomedical Engineering and Physics, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
authors: Nadja
authors: N
authors: Nijenhuis
authors: Daisuke
authors: D
authors: Mizuno
authors: Jos A E
authors: JA
authors: Spaan
authors: Christoph F
authors: CF
authors: Schmidt
mesh_terms: D053674:Aggrecans / Q000737:chemistry; D000818:Animals; D001696:Biomechanical Phenomena; D002417:Cattle; D002809:Chondroitin Sulfates / Q000737:chemistry; D042783:Endothelial Cells / Q000737:chemistry*; D019276:Glycocalyx / Q000737:chemistry*; D006497:Heparan Sulfate / Q000737:chemistry; D006820:Hyaluronic Acid / Q000737:chemistry*; D008954:Models, Biological; D010949:Plasma / Q000737:chemistry; D012212:Rheology; D012710:Serum Albumin, Bovine / Q000737:chemistry; D033081:Shear Strength; D055682:Viscoelastic Substances / Q000737:chemistry*
chemical_list: D053674:Aggrecans; D002809:Chondroitin Sulfates; D006497:Heparan Sulfate; D006820:Hyaluronic Acid; D012710:Serum Albumin, Bovine; D055682:Viscoelastic Substances