Modulation of Endothelial Cell Expression of ICAM-1, E-Selectin, and VCAM-1 by β-Estradiol, Progesterone, and Dexamethasone

The aim of this study was to examine the effects of β-estradiol, progesterone, and dexamethasone on cytokine-stimulated endothelial cell expression of adhesion molecules. TNF-α (250 U/ml) and IL-1α (50 U/ml) were used to stimulate the endothelial cells for 6 or 23 hrin vitro.Indirect immunofluorescence and flow cytometry were used to quantitate expression of adhesion molecules. After 6 hr stimulation with TNF-α increased expression of E-selectin (P< 0.03) was noted with β-estradiol. Strong suppression of ICAM-1 (P< 0.005) and E-selectin (P< 0.005) expression was evident with dexamethasone, which did not influence VCAM-1 expression. After 6 hr stimulation with IL-1α suppression of E-selectin was observed with progesterone (P< 0.001). Dexamethasone had strong suppressive effects on ICAM-1 (P< 0.001), E-selectin (P< 0.0001), and VCAM-1 (P< 0.0002). After 23 hr stimulation with IL-1α or TNF-α none of the examined steroids showed a significant effect on the fluorescence intensity of adhesion molecules, although there was a slight increase of the percentage of ICAM-1-positive cells with high concentrations of β-estradiol after stimulation with TNF-α. β-Estradiol and progesterone are modulatory factors of E-selectin expression on endothelial cellin vitro.Dexamethasone reduces adhesion molecule expression over endothelial cells after cytokine stimulation. These effects may be important in understanding the role of these steroids in autoimmune diseases.