Involvement of proteinase-activated receptor-2 in mast cell tryptase-induced barrier dysfunction in bovine aortic endothelial cells

• Published in: Cellular signalling 2003-08, Vol.15 (8), p.773-781
• Main Authors: Sendo, Toshiaki, Sumimura, Tomoko, Itoh, Yoshinori, Goromaru, Takeshi, Aki, Keisei, Yano, Takahisa, Oike, Masahiro, Ito, Yushi, Mori, Shuji, Nishibori, Masahiro, Oishi, Ryozo
• Format: Article
• Language: English
• Subjects: Actin stress fibre; Actins - drug effects; Actins - metabolism; Anaphylaxis - chemically induced; Anaphylaxis - metabolism; Anaphylaxis - physiopathology; Animals; Antigens, CD; Aorta - cytology; Bovine aortic endothelial cells; Cadherins - metabolism; Calcium Signaling - drug effects; Calcium Signaling - physiology; Capillary Permeability - drug effects; Capillary Permeability - physiology; Cattle; Cells, Cultured; Contrast Media - adverse effects; Dose-Response Relationship, Drug; Endothelial Cells - drug effects; Endothelial Cells - metabolism; Enzyme Inhibitors - pharmacology; Evans Blue; Gabexate - pharmacology; Guanidines - pharmacology; Ioxaglic Acid - pharmacology; Mast cell tryptase; Nafamostat; Proteinase-activated receptor-2; Receptor, PAR-2 - drug effects; Receptor, PAR-2 - metabolism; Serine Endopeptidases - metabolism; Serine Endopeptidases - pharmacology; Stress Fibers - drug effects; Stress Fibers - metabolism; Tryptases; VE-cadherin
• ISSN: 0898-6568; 1873-3913
• DOI: 10.1016/S0898-6568(03)00014-7

We report here a direct modulation by mast cell tryptase of endothelial barrier function through activation of proteinase-activated receptor-2 (PAR-2). In cultured bovine aortic endothelial cells (BAECs), tryptase, trypsin and PAR-2 activating peptide impaired the barrier function as determined by the permeability of protein-conjugated Evans blue. The tryptase-induced barrier dysfunction was completely blocked by U73122, and partially reversed by xestospongin C, calphostin C or Y27632. The intracellular Ca 2+ was elevated by tryptase. It was notable that ioxaglate, a contrast material that degranulates mast cells, markedly increased the permeability when applied to BAECs in combination with mast cells, an action that was blocked by nafamostat, a potent tryptase inhibitor. Immnofluorescence analysis showed that actin stress fibre formation and disruption of VE-cadherin were observed after exposure to tryptase or ioxaglate in combination with mast cells. Therefore, it is suggested that mast cell tryptase impairs endothelial barrier function through activation of endothelial PAR-2 in a manner dependent on the phospholipase C activity.