Dexamethasone reduces lung eosinophilia, and VCAM-1 and ICAM-1 expression induced by Sephadex beads in rats.
Airway eosinophilia is one of the key pathophysiologic features in asthma. The endothelial adhesion molecules, vascular cell adhesion molecule (VCAM-1) and intercellular adhesion molecule (ICAM-1), have previously been shown to play a crucial role in eosinophil recruitment into the inflamed airway. We have investigated the effects of dexamethasone on eosinophilia into the bronchoalveolar lavage fluid, and the upregulation of VCAM-1 and ICAM-1 expression, measured by immunoblotting, induced by i.v. injection of Sephadex beads into rats. The beads significantly increased the lung eosinophilia, and expression of VCAM-1 and ICAM-1 in the lung. Pretreatment with dexamethasone (0.1 to 2 mg/kg i.p.) strongly inhibited all the airway inflammatory events in a dose-dependent manner. In conclusion, glucocorticoids may be potent inhibitors of lung eosinophilia, at least in part, due to the prevention of the upregulation of VCAM-1 and ICAM-1 expression.
Department of Pediatrics, Nagoya University Postgraduate School of Medicine, 65 Tsurumai-cho, Showa, Nagoya 466-8550, Japan.
Akemi
A
Ito
Mio
M
Miyake
Masashi
M
Morishita
Komei
K
Ito
Shinpei
S
Torii
Tatsuo
T
Sakamoto
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology / Q000276:immunology; D003907:Dexamethasone / Q000494:pharmacology*; D003911:Dextrans / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D004802:Eosinophilia / Q000139:chemically induced / Q000378:metabolism / Q000517:prevention & control*; D015151:Immunoblotting; D018799:Intercellular Adhesion Molecule-1 / Q000276:immunology / Q000378:metabolism*; D007958:Leukocyte Count; D008297:Male; D011014:Pneumonia / Q000139:chemically induced / Q000378:metabolism / Q000517:prevention & control*; D051381:Rats; D017208:Rats, Wistar; D019010:Vascular Cell Adhesion Molecule-1 / Q000276:immunology / Q000378:metabolism*
D000893:Anti-Inflammatory Agents; D003911:Dextrans; D019010:Vascular Cell Adhesion Molecule-1; D018799:Intercellular Adhesion Molecule-1; D003907:Dexamethasone; C025614:sephadex