Modulation of the inflammatory response by estrogens with focus on the endothelium and its interactions with leukocytes.

Gender differences and variations in inflammatory disease (e. g. atherosclerosis, neurological disorders, periodontitis and rheumatoid arthritis) severity with female sex hormone level have been reported, suggesting that female sex hormones modulate the inflammatory response. Estrogens act on gene transcription via estrogen receptors alpha and beta. Identification of estrogen-regulated genes is a matter of great interest since it will contribute significantly to the understanding of the physiological importance of estrogens. Anti-inflammatory as well as pro-inflammatory responses to estrogens have been reported. Data have been presented showing that estrogens down-regulate the expression of adhesion and chemokine molecules in response to inflammation promoters in various experimental systems. Functional data show that estrogen treatment attenuates recruitment and adhesion of leukocytes to the endothelium induced by inflammation promoters offering a possible mechanism by which estrogens exert an anti-inflammatory effect. These effects of estrogens, with focus on the interactions of monocytes with the vascular endothelium, are highlighted in this review.