Page 27 - HKSEMR2020 Programme book

Poster Presentation (Basic Science) Abstracts

The role of adrenomedullin on placental development during early

pregnancy and its association with early-onset preeclampsia

Qing-Qing Zhang, Cheuk-Lun Lee, Philip C.N. Chiu
Department of Obstetrics and Gynecology, The University of Hong Kong, Pokfulam Road, Hong Kong SAR;
Shenzhen Key Laboratory of Fertility Regulation, Department of Obstetrics and Gynecology, The University of Hong
Kong-Shenzhen Hospital

Introduction / Background / Objectives: into and replace the vascular endothelium, an in vitro trophoblast-
endothelial cells co-culture model was employed. Adrenomedullin
Remodelling of the maternal spiral arteries is crucial to placenta
formation and successful pregnancy. Dysregulation of the expression in the primary placental tissues was determined by
process is associated with pregnancy complications that lead immunohistochemistry. The role of adrenomedullin in placental
to significant maternal and fetal death. Preeclampsia, one of the development was also validated in vivo using a mouse model.
complications characterized by insufficient spiral artery remodeling
during early pregnancy, affects 2-5% of all pregnancies and is Results / Outcomes:
the leading cause of prenatal mortality and morbidity. Currently,
there is no reliable approach for either prediction or treatment of Adrenomedullin treatment significantly (P < 0.05) increased the
preeclampsia. migration, invasion and integration along the vascular endothelial
lining of primary trophoblast compared to controls. These actions
Adrenomedullin is a peptide hormone most abundantly expressed of adrenomedullin were completely blocked by the administration
in the human placenta during early pregnancy. Although previous of human adrenomedullin receptor antagonists. Adrenomedullin
data from animal models support a role for adrenomedullin in expression was reduced in the first trimester placental samples
placental vascular remodelling, its role in human pregnancy is from early-onset preeclampsia patients compared with normal
unknown.
pregnancy controls. A similar pattern of reduced adrenomedullin
We hypothesize that adrenomedullin regulates the placental expression was found in term placental tissues between normal
vascular remodeling process in humans by modulating the and early-onset preeclampsia pregnancies. Placenta-specific
activities of trophoblast during early pregnancy, and that the down- knockdown of adrenomedullin induced extensive placental
regulation of adrenomedullin contributes to the pathophysiology of haemorrhage, fetal resorption, reduced fetus weight, and defective
preeclampsia. placental development in pregnant mice compared with controls.

Methods: Conclusion:
This study was approved by the Institutional Review Board of Our data suggest the involvement of adrenomedullin in regulating
the University of Hong Kong/Hospital Authority Hong Kong West placental development by modulating the activities of trophoblast.
Cluster. Human trophoblast was isolated from the first trimester The down-regulation of adrenomedullin contributed to the
placental tissues using our established protocol. Trophoblast pathophysiology of preeclampsia. The results of this study indicate
invasion and migration were evaluated by transwell assay. The the potential use of adrenomedullin levels as a test for early
effect of adrenomedullin on angiogenesis was determined by tube prediction of preeclampsia.
formation assay. To model the ability of trophoblast to integrate

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