Hypoxia Promotes Interleukin-6 and -8 but Reduces Interleukin-10 Production by Placental Trophoblast Cells From Preeclamptic Pregnancies

Abstract

Objective: Placental hypoxia and altered placental cytokine productions have been considered to play a significant role in the pathophysiology of preeclampsia. The objective of this study was to determine whether hypoxia could modify interleukin (IL)-6, IL-8, and IL-10 production by placental trophoblast cells (TCs) from normal and preeclamptic (PE) pregnancies.

Methods: Placentas were obtained from nine normal and nine PE pregnancies immediately after delivery. Placental TCs were isolated and cultured under normoxic (21% O₂/air) and hypoxic (2% O₂/5% CO₂/92% N₂) conditions for 48 hours. TC productions of IL-6, IL-8, and IL-10 were measured by enzyme-linked immunosorbent assay (ELISA). Unpaired t tests or paired t test was used for the statistical analysis and data are expressed as means ± SE (pg/μg cellular protein). A P value less than .05 was considered statistically significant.

Results: PE-TCs produced significantly more IL-6, IL-8, and IL-10 than those of normal-TCs when they were cultured under normoxic condition, P < .05.> Both normal-TCs and PE-TCs produced more IL-6 and IL-8 when they were cultured under hypoxic conditions. Hypoxia reduced IL-10 production by PE-TCs, but had no effect on IL-10 production by normal-TCs.

Conclusions: Hypoxia promotes both IL-6 and IL-8 but reduces IL-10 production by placental TCs from PE pregnancies.

Keywords

Cytokine trophoblast preeclampsia hypoxia

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