Interleukin (IL)-6, is one of the main pro-inflammatory mediators of hypertension and endothelial dysfunction in preeclampsia. In the current study, we investigated the capacity of the preeclamptic placenta to secrete IL-6 and the effect of magnesium sulfate (MgSO4) on it.

Placentas from normotensive (N) (37-40 weeks) and preeclamptic (PE) (36-40 weeks) pregnancies were dually perfused for 6 hours in absence [N (n=3); PE (n=4)] and presence [N (n=3); PE (n=4)] of MgSO4.

Perfusate samples from the maternal and the fetal circulations were collected each 30 min through all the perfusion and examined for IL-6 by ELISA. Statistical analysis was performed using the two-way analysis of variance (ANOVA).

In absence of MgSO4, IL-6 levels in the maternal and the fetal circulations of preeclamptic placentas (4.2±1.3 pg/ml/gr cotyledon and 0.9±0.5 pg/ml/gr cotyledon; respectively) were significantly higher, as compared to normotensive placentas (1.9±0.5 pg/ml/gr cotyledon and 0.2±0.2 pg/ml/gr cotyledon; respectively) (p<0.05). Addition of MgSO4 to the perfusate of normotensive placentas did not affect IL-6 secretion.

However, exposure of preeclamptic placentas to MgSO4 resulted in decreased IL-6 levels in the maternal circulations (1.7±0.3 pg/ml/gr cotyledon), as compared to control group (p<0.05).

On the fetal circulation, the addition of MgSO4 resulted only in a non-statistical significant tendency toward decreased IL-6 levels, as compared to control group. Our findings indicate that the perfused preeclamptic placenta secretes increased levels of IL-6 into the fetal and the maternal circulations, and that MgSO4 may normalize these increased secreted IL-6 levels.

Authors

Alaa Amash^1,2, Gershon Holcberg ^2,3, Eyal Sheiner ^2,3, Mahmoud Huleihel ¹,²¹

The Shraga Segal Department of Microbiology and Immunology, ² Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
³ Departments of Obstetrics and Gynecology, Soroka University Medical Center, Beer Sheva, Israel