Increased annexin A2 expression in the placenta of women with acute worsening of preeclampsia

Abstract

Background: The aims of present study were to investigate the expression of Annexin A2 in the placenta of patients with preeclampsia (PE) and correlate these data with acute worsening of clinical symptoms.

Methods: Placentas were collected from uncomplicated normal pregnancies (n = 9), PE cases without emergency termination of pregnancy (group 1, n = 6), and PE cases with acute worsening of symptoms necessitating immediate pregnancy termination (group 2, n = 7). Immunohistochemistry data were analyzed quantitatively, and placental mRNA expression was measured by Real-time PCR.

Results: Group 2 had a significantly shorter interval between diagnosis and pregnancy termination compared with group 1 (p = 0.002). Birth weight and placental weight in group 2 were significantly lower compared with the normal group (p = 0.006 and p = 0.03, birth weight and placental weight, respectively), whereas there were no differences in gestational age at delivery between the three groups or the severity of high blood pressure and proteinuria between the PE groups. Placental expression of Annexin A2 as determined by immunohistochemistry was significantly higher in both PE groups compared with the uncomplicated pregnancy group (p < 0.001 and p < 0.001, groups 1 and 2, respectively). Placental Annexin A2 mRNA expression was significantly elevated in group 2 compared with the normal group (p = 0.002) but did not change in group 1.

Conclusions: This study is the first to demonstrate increased placental Annexin A2 mRNA expression during the acute phase of PE. Immunohistochemical staining of placental Annexin A2 was high, regardless of PE phase. These findings suggest that worsening of PE might alter Annexin A2 expression at the transcription level.