2-Methoxyoestradiol levels and placental catechol-O-methyltransferase expression in patients with late-onset preeclampsia

Abstract

Deficiencies in placental catechol-O-methyltransferase (COMT) and circulating 2-methoxyoestradiol (2-ME) have been shown to be related to early onset preeclampsia. The aim of this study was to investigate levels of 2-ME in the serum and urine of patients with late-onset preeclampsia and to compare those levels to those of normal pregnant women. In addition, we examined placental COMT expression in both groups. Fifteen patients with preeclampsia and 15 normal pregnant women were enrolled. 2-ME levels were evaluated by ELISA and placental COMT expression was examined by Western blot analysis. 2-ME levels in serum [median 181.1 pg/mL, interquartile range (IQR) 119.6-244.3 vs. 61.2 pg/mL, IQR 12.0-133.7, respectively, p = 0.004] and urine (median 143.3 pg/mL, IQR 35.0-328.2 vs. 0.5 pg/mL, IQR 0.4-4.6, respectively, p < 0.001) were significantly increased in patients with late-onset preeclampsia compared to those in normal pregnant women at term. There was no significant difference in placental COMT expression between the two groups. Increased levels of 2-ME in patients with late-onset preeclampsia might be a product of a compensatory mechanism in patients with late-onset preeclampsia.