Increase of serum angiopoietin-2 during pregnancy is suppressed in women with preeclampsia.
BACKGROUND
Numerous recent reports demonstrated that changes in serum levels of angiogenesis-related factors were associated with preeclampsia. Here, we determined the serum concentration of angiopoietin-2 (Ang-2), a natural antagonist of angiopoietin-1 (Ang-1) involved in promoting angiogenesis in the presence of angiogenic stimuli such as vascular endothelial growth factor (VEGF), in women with preeclampsia.


METHODS
The levels of serum Ang-2 and Tie-2, a receptor for Ang-1 expressed on endothelial cells, were determined by enzyme-linked immunosorbent assay.


RESULTS
The concentrations of serum Ang-2 were significantly elevated in healthy pregnant women (18.9 ng/mL) as compared to nonpregnant women or women in postpartum period. Increase in the levels of serum Ang-2 was significantly suppressed in preeclamptic women (4.5 ng/mL). The serum Ang-2 concentrations inversely correlated with gestational age in healthy pregnant women, but not in preeclamptic women. The serum Ang-2 concentrations positively correlated with placental weight or mean blood pressure (BP) in healthy pregnant women, but not in preeclamptic women. The serum Ang-2 concentrations inversely correlated with proteinuria in preeclamptic women. The serum concentrations of Tie-2 were not significantly different between preeclamptic and nonpreeclamptic women.


CONCLUSIONS
These results suggest the potential requirement of circulating Ang-2 in proper formation of placental vasculatures during pregnancy. Although we cannot exclude the possibility that suppression in the increase of serum Ang-2 levels during pregnancy in preeclampsia as a consequence rather than a cause, measurement of serum Ang-2 concentration in pregnant women may serve as a useful marker in the diagnosis and potentially in predicting subsequent development of preeclampsia.
Hirokoshi
Kumiko
K
Department of Medicine and Clinical Science, Okayama University Graduate School of Medicine and Dentistry, 2-5-1 Shikata-cho, Okayama 700-8558, Japan.
Maeshima
Yohei
Y
Kobayashi
Kazuko
K
Matsuura
Eiji
E
Sugiyama
Hitoshi
H
Yamasaki
Yasushi
Y
Masuyama
Hisashi
H
Hiramatsu
Yuji
Y
Makino
Hirofumi
H
D000328:Adult; D042702:Angiopoietin-2 / Q000097:blood*; D001794:Blood Pressure / Q000502:physiology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D009929:Organ Size; D010920:Placenta / Q000033:anatomy & histology; D011225:Pre-Eclampsia / Q000097:blood* / Q000503:physiopathology; D011247:Pregnancy; D042787:Receptor, TIE-2 / Q000097:blood
D042702:Angiopoietin-2; D042787:Receptor, TIE-2