Potential role of MCP-1 in endothelial cell tight junction 'opening': signaling via Rho and Rho kinase.
The expression of the monocyte chemoattractant protein-1 (MCP-1) receptor CCR2 by brain endothelial cells suggests that MCP-1 may have other functions than purely driving leukocyte migration into brain parenchyma during inflammation. This study examines one of these potential novel roles of MCP-1 regulation of endothelial permeability using primary cultures of mouse brain endothelial cells. MCP-1 induces reorganization of actin cytoskeleton (stress fiber formation) and redistribution of tight junction proteins, ZO-1, ZO-2 occludin and claudin-5, from the Triton X-100-soluble to the Triton X-100-insoluble fractions. These morphological changes are associated with a decrease in transendothelial electrical membrane resistance and an increase in [14C]inulin permeability. MCP-1 did not induce these events in brain endothelial cells prepared from mice genotype CCR2-/-. The Rho kinase inhibitor Y27632 and inhibition of Rho (C3 exoenzyme, and dominant negative mutant of Rho, RhoT19N) prevented MCP-1-induced stress fiber assembly, reorganization of tight junction proteins and alterations in endothelial permeability. In all, this suggests that a small GTPase Rho and Rho kinase have a pivotal role in MCP-1-induced junction disarrangement. These data are the first to strongly suggest that MCP-1, via CCR2 present on brain endothelial cells, contributes to increased brain endothelial permeability.
Department of Neurosurgery, University of Michigan Medical School, Ann Arbor, MI 48109, USA.
Svetlana M
SM
Stamatovic
Richard F
RF
Keep
Steven L
SL
Kunkel
Anuska V
AV
Andjelkovic
D000209:Acute-Phase Proteins / Q000378:metabolism*; D000818:Animals; D001921:Brain / Q000378:metabolism; D002478:Cells, Cultured; D018932:Chemokine CCL2 / Q000378:metabolism*; D062507:Claudin-5; D017097:Electric Impedance; D042783:Endothelial Cells / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins; D007444:Inulin / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D008856:Microscopy, Fluorescence; D009154:Mutation; D062793:Occludin; D017830:Octoxynol / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D010539:Permeability / Q000187:drug effects*; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D054390:Receptors, CCR2; D019707:Receptors, Chemokine / Q000378:metabolism; D022502:Stress Fibers / Q000378:metabolism; D019108:Tight Junctions / Q000378:metabolism*; D062827:Zonula Occludens-2 Protein; D054460:rho-Associated Kinases
D000209:Acute-Phase Proteins; C515335:Ccr2 protein, mouse; D018932:Chemokine CCL2; D062507:Claudin-5; C491511:Cldn5 protein, mouse; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D062793:Occludin; C568986:Ocln protein, mouse; D054390:Receptors, CCR2; D019707:Receptors, Chemokine; C569047:Tjp2 protein, mouse; D062827:Zonula Occludens-2 Protein; C010781:acute-phase protein rho; D017830:Octoxynol; D007444:Inulin; D017346:Protein Serine-Threonine Kinases; D054460:rho-Associated Kinases