Spontaneous and induced release of prostaglandins, interleukin (IL)-1beta, IL-6, and tumor necrosis factor-alpha by placental tissue from normal and preeclamptic pregnancies

PROBLEM: The objective of this study was to clarify the role of the main proinflammatory cytokines (interleukin [IL]-1, IL-6, tumor necrosis factor [TNF]-alpha) in the pathogenesis of preeclampsia and how these cytokines affect one another and the production of prostaglandins (PGs). METHOD OF STUDY: The concentrations of cytokines and PGs in supernatants of placental tissue from preeclamptic and normal women were determined by enzyme-linked immunosorbent assay. RESULTS: The concentrations of the PGs from unstimulated preeclamptic placental tissue were significantly higher compared to the concentrations of PGs from normal unstimulated placental tissue. Significant levels of IL-1beta were observed only in the supernatants of preeclamptic placental tissue. Of interest, an increase in TNF-alpha production was detected in the supernatants of IL-1-stimulated preeclamptic placental tissue. CONCLUSIONS: The overproduction of TNF-alpha may be related not only to the effect of a stimulant like IL-1beta, but mainly to the lack of mechanisms down-regulating the production of TNF-alpha.