title: Endothelial permeability is controlled by spatially defined cytoskeletal mechanics: atomic force microscopy force mapping of pulmonary endothelial monolayer.
abstract: Actomyosin contraction directly regulates endothelial cell (EC) permeability, but intracellular redistribution of cytoskeletal tension associated with EC permeability is poorly understood. We used atomic force microscopy (AFM), EC permeability assays, and fluorescence microscopy to link barrier regulation, cell remodeling, and cytoskeletal mechanical properties in EC treated with barrier-protective as well as barrier-disruptive agonists. Thrombin, vascular endothelial growth factor, and hydrogen peroxide increased EC permeability, disrupted cell junctions, and induced stress fiber formation. Oxidized 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine, hepatocyte growth factor, and iloprost tightened EC barriers, enhanced peripheral actin cytoskeleton and adherens junctions, and abolished thrombin-induced permeability and EC remodeling. AFM force mapping and imaging showed differential distribution of cell stiffness: barrier-disruptive agonists increased stiffness in the central region, and barrier-protective agents decreased stiffness in the center and increased it at the periphery. Attenuation of thrombin-induced permeability correlates well with stiffness changes from the cell center to periphery. These results directly link for the first time the patterns of cell stiffness with specific EC permeability responses.
authors.affiliation: Division of Biomedical Sciences, Department of Medicine, Section of Pulmonary and Critical Care Medicine University of Chicago, Chicago, Illinois 60637, USA.
authors.forename: Anna A
authors.initials: AA
authors.lastname: Birukova
authors.forename: Fernando T
authors.initials: FT
authors.lastname: Arce
authors.forename: Nurgul
authors.initials: N
authors.lastname: Moldobaeva
authors.forename: Steven M
authors.initials: SM
authors.lastname: Dudek
authors.forename: Joe G N
authors.initials: JG
authors.lastname: Garcia
authors.forename: Ratnesh
authors.initials: R
authors.lastname: Lal
authors.forename: Konstantin G
authors.initials: KG
authors.lastname: Birukov
mesh_terms: D002460:Cell Line; D003599:Cytoskeleton / Q000187:drug effects / Q000378:metabolism*; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D005455:Fluorescent Antibody Technique; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D008168:Lung / Q000098:blood supply / Q000166:cytology*; D018625:Microscopy, Atomic Force / Q000379:methods*; D008856:Microscopy, Fluorescence; D010539:Permeability / Q000187:drug effects; D010713:Phosphatidylcholines / Q000494:pharmacology; D013917:Thrombin / Q000494:pharmacology; D042461:Vascular Endothelial Growth Factor A / Q000494:pharmacology
chemical_list: C468114:1-palmitoyl-2-arachidonyl-3-phosphorylcholine; D010713:Phosphatidylcholines; D042461:Vascular Endothelial Growth Factor A; D006861:Hydrogen Peroxide; D013917:Thrombin