title: Rho inhibition decreases TNF-induced endothelial MAPK activation and monolayer permeability.
abstract: Our laboratory previously demonstrated that MAPK activation is an important signal during cytokine-induced endothelial permeability (Nwariaku FE, Liu Z, Terada L, Duffy S, Sarosi G, and Turnage R. Shock 18: 82-85, 2002). Because GTP-binding proteins have been implicated in MAPK activation, we now hypothesize that the GTP-binding protein Rho is a mediator of TNF-induced MAPK activation and increased endothelial permeability. Transmonolayer permeability was assessed in human lung microvascular cells by measuring transmonolayer electrical resistance. MAPK activity was assessed by using a phospho-specific immunoprecipitation kinase assay and by comparing Western blots for phospho-MAPK with total MAPK. MAPK inhibitors used were SB-202190 and PD-098059, whereas Clostridium botulinum C3 transferase was used as a Rho inactivator. Rho-associated coiled-coil kinase was inhibited with Y-27632. TNF increased pulmonary endothelial permeability in vitro and caused a rapid, sustained increase in endothelial p38 and extracellular signal-regulated kinase MAPK activity. Inhibition of p38 and extracellular signal-regulated kinase MAPK with SB-202190 and PD-098059, respectively, decreased TNF-induced endothelial permeability. C3 transferase attenuated TNF-induced MAPK activation and blocked TNF-induced endothelial permeability. Finally, inhibition of Rho-associated coiled-coil kinase with Y-27632 prevented both MAPK activation and TNF-induced decreases in transmonolayer resistance. Rho acts upstream of mitogen-activated protein kinases in mediating TNF-induced pulmonary endothelial leak.
authors.affiliation: Department of Surgery, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9156, USA. fiemu.nwariaku@UTSouthwestern.edu
authors.forename: Fiemu E
authors.initials: FE
authors.lastname: Nwariaku
authors.forename: Patricia
authors.initials: P
authors.lastname: Rothenbach
authors.forename: Zijuan
authors.initials: Z
authors.lastname: Liu
authors.forename: Xudong
authors.initials: X
authors.lastname: Zhu
authors.forename: Richard H
authors.initials: RH
authors.lastname: Turnage
authors.forename: Lance S
authors.initials: LS
authors.lastname: Terada
mesh_terms: D036002:ADP Ribose Transferases / Q000494:pharmacology; D000577:Amides / Q000494:pharmacology; D000970:Antineoplastic Agents / Q000494:pharmacology*; D001905:Botulinum Toxins / Q000494:pharmacology; D002199:Capillary Permeability / Q000187:drug effects / Q000502:physiology; D002460:Cell Line; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects / Q000201:enzymology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D008168:Lung / Q000098:blood supply; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D011725:Pyridines / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D048051:p38 Mitogen-Activated Protein Kinases; D020741:rho GTP-Binding Proteins / Q000037:antagonists & inhibitors* / Q000378:metabolism
chemical_list: D000577:Amides; D000970:Antineoplastic Agents; D004791:Enzyme Inhibitors; D011725:Pyridines; D014409:Tumor Necrosis Factor-alpha; C108830:Y 27632; D036002:ADP Ribose Transferases; C063007:exoenzyme C3, Clostridium botulinum; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D001905:Botulinum Toxins; D020741:rho GTP-Binding Proteins