Oral estrogen treatment induces a decrease in expression of sialyl Lewis x on α₁ glycoprotein in females and male-to-female transsexuals

Abstract

The effect of estrogen on the glycosylation of alpha 1-acid glycoprotein was studied in women using oral contraceptives and in male-to-female transsexuals receiving oral or transdermal estrogen treatment. Oral estrogen treatment induced an increase in degree of branching and a decrease in fucosylation and sialyl Lewis x expression on alpha 1-acid glycoprotein compared to individuals receiving no estrogens or transdermal estrogen treatment. The effect on the glycosylation of alpha 1-acid glycoprotein was less in the male-to-female transsexuals receiving oral estrogens in combination with cyproterone acetate, a blocker of the androgen receptor with progestagen-like effects. This was of comparable magnitude as in women using oral contraceptives containing both estrogen and progestagen. We conclude that oral estrogens have an identical effect on the hepatic glycosylation of alpha 1-acid glycoprotein in both males and females and that progestagen reduces this effect. These results show that oral estrogens induce an effect on the glycosylation of alpha 1-acid glycoprotein opposite to that induced by inflammation. Oral estrogens can therefore modulate the glycosylation dependent inflammatory actions of alpha 1-acid glycoprotein, while this is not the case with transdermal estrogens. In all likelihood, estrogen receptors on the hepatocyte must play a significant role in the observed effect.

Proteomic Analysis to Identify Breast Cancer Biomarkers in Nipple Aspirate Fluid

“…In postmenopausal women, unopposed estrogen use was associated with modestly lower levels of AAG (29). This is consistent with our finding of higher levels in postmenopausal women without breast cancer, most of whom have very low levels of circulating estradiol, and with the fact that oral estrogen treatment lowers AAG levels in the blood (30). Positive immunoreactivity for GCDFP-15 in breast tumors was found to be highly dependent on androgen receptor status, but unrelated to estrogen or progesterone receptor (31).…”

Nutrition and human health from a sex–gender perspective

“…Albumin concentrations do not consistently vary by sex, but AAG levels and AAG-glycosylation states vary in association with endogenous and exogenous estrogens (Brinkman- Van der Linden et al, 1996;Succari et al, 1990;Walle et al, 1994), which both decrease levels of AAG in the plasma and induce hepatic glycosylation of these proteins (Brinkman- Van der Linden et al, 1996). In addition, exogenous estrogens increase the levels of the serum-binding globulins, which include sex hormone-binding globulins, corticosteroid-binding globulin, and thyroxinebinding globulin (Wiegratz et al, 2003).…”

The Acute Phase Protein α1-Acid Glycoprotein: A Model for Altered Glycosylation During Diseases

“…b) The analysis of the degree of fucosylation of AGP has been carried out mainly by means of interaction with Aleuria aurantia lectin (AAL) [53], a fucose-specific lectin. This lectin is generally chosen for its specificity for (1-6)-linked fucose residues.…”