Objective: To determine the role of the placenta in controlling the circulatory levels of IL-1β and its natural inhibitor IL-1 receptor antagonist (RA), and to study the effect of magnesium sulfate (MgSO4) on these levels.
Methods: Using an ex-vivo placental perfusion system, human placentas from preeclamptic (n=9) and normotensive (n=6) pregnancies were perfused in presence or absence of MgSO4. Perfusate samples were collected from the maternal and the fetal circulation of the perfusion system, and IL-1β and IL-1RA were examined by ELISA.
Results: Placentas from preeclamptic pregnancies secreted increased levels of IL-1β and IL-1RA into the fetal and the maternal circulations, as compared to normotensive placentas. However, no differences in IL-1β:IL-1RA ratio were detected in the fetal or the maternal circulations. Administration of MgSO4 to preeclamptic placentas resulted in attenuation of the increased secretion of IL-1β in the maternal circulation and of IL-1RA in both the maternal and the fetal circulation. Nevertheless, IL-1β:IL-1RA ratio was not affected by MgSO4. Paradoxically, exposure of normotensive placenta to MgSO4 resulted only in increased levels of IL-1RA in the fetal and the maternal circulations.
Conclusions: Although the increased placental secretion of IL-1β and IL-1RA in preeclampsia, the placenta doesn’t seem to play a critical role in disrupting the balance in maternal IL-1β:IL-1RA ratio in this disorder. Moreover, IL-1β and IL-1RA seem to be not involved in the mechanism of action of MgSO4 in preeclampsia.
Tamar Eshkoli1, Alaa Amash2, Mahmoud Huleihel2,*, Eyal Sheiner1, Gershon Holcberg1,*.
1Department of Obstetrics and Gynecology, Soroka University Medical Center, Beer-Sheva, Israel; 2The Shraga Segal Department of Microbiology and Immunology, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
*These two authors contributed equally to this work