Involvement of Rho signaling in PAR2-mediated regulation of neutrophil adhesion to lung epithelial cells.
Protease-activated receptor 2 (PAR2) has been implicated in the pathogenesis of airway inflammation. We report that epithelial PAR2 stimulation with trypsin (0.05-1 U/ml) or an agonist peptide (SLIGKV-NH2, 1-100 microM) for 0.5-3 h dose- and time-dependently enhanced neutrophil adhesion to alveolar type II epithelial cells (A549 cells) and that this stimulation also induced the formation of epithelial actin filaments. Both responses in neutrophil adhesion and epithelial actin reorganization were reduced by a Rho inhibitor, mevastatin and by a Rho-associated kinase (ROCK) inhibitor, Y-27632 ((R)-(+)-trans-N-(4-Pyridyl)-4-(1-aminoethyl)-cyclohexanecarboxamide). Neutrophil adherence was also inhibited by an inhibitor of actin polymerization, cytochalasin D and a tyrosine kinase inhibitor, genistein. Further, the PAR2-mediated tyrosine phosphorylation of focal adhesion kinase (FAK), a major cytoskeleton protein, was detected, and this response was inhibited by mevastatin or Y-27632. These results suggest that PAR2 stimulation of alveolar epithelial cells enhances neutrophil adhesion presumably at least in part through Rho/ROCK signal-mediated actin cytoskeleton reorganization associated with the tyrosine phosphorylation of FAK.
Department of Pharmacology, Kansai Medical University, Moriguchi Osaka 570-8506, Japan.
Yasuhiro
Y
Yagi
Hitomi
H
Otani
Seijitsu
S
Ando
Akihiro
A
Oshiro
Kenzo
K
Kawai
Hiroyuki
H
Nishikawa
Hiromasa
H
Araki
Shirou
S
Fukuhara
Chiyoko
C
Inagaki
D008841:Actin Cytoskeleton / Q000187:drug effects / Q000378:metabolism; D000577:Amides / Q000494:pharmacology; D002448:Cell Adhesion / Q000187:drug effects; D045744:Cell Line, Tumor; D015638:Cytochalasin D / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004847:Epithelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D051416:Focal Adhesion Protein-Tyrosine Kinases / Q000378:metabolism; D019833:Genistein / Q000494:pharmacology; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D008168:Lung / Q000166:cytology; D009504:Neutrophils / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D009842:Oligopeptides / Q000494:pharmacology; D010766:Phosphorylation / Q000187:drug effects; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D011725:Pyridines / Q000494:pharmacology; D044464:Receptor, PAR-2 / Q000819:agonists / Q000502:physiology*; D015398:Signal Transduction; D013997:Time Factors; D014357:Trypsin / Q000494:pharmacology; D054460:rho-Associated Kinases
D000577:Amides; D004791:Enzyme Inhibitors; D047908:Intracellular Signaling Peptides and Proteins; D009842:Oligopeptides; D011725:Pyridines; D044464:Receptor, PAR-2; C109968:seryl-leucyl-isoleucyl--glycyl-lysyl-valine; C108830:Y 27632; D015638:Cytochalasin D; D019833:Genistein; D051416:Focal Adhesion Protein-Tyrosine Kinases; D017346:Protein Serine-Threonine Kinases; D054460:rho-Associated Kinases; D014357:Trypsin