Expression levels of cyclooxygenase-2, tumor necrosis factor-alpha and inducible NO synthase in placental tissue of normal and preeclamptic pregnancies

Erol A. Y. G. , Nazli M., Yildiz S. E.

JOURNAL OF MATERNAL-FETAL & NEONATAL MEDICINE, vol.25, no.6, pp.826-830, 2012 (Journal Indexed in SCI) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 25 Issue: 6
  • Publication Date: 2012
  • Doi Number: 10.3109/14767058.2011.595853
  • Page Numbers: pp.826-830


Objective: Although preeclampsia (PE) is one of the most important problems affecting pregnant women, etiologic factors in its development are still unclear. We aimed to investigate the expression levels of cyclooxygenase-2 (COX-2), tumor necrosis factor-alpha (TNF-alpha) and inducible NO synthase (iNOS) in preeclamptic and healthy control placentas. Patients and methods: Placental tissue samples were obtained after delivery from patients diagnosed with PE and from normal-term pregnants and analyzed for COX-2, TNF-alpha and iNOS expression by immunohistochemistry. Results: A strong expression of COX-2 was observed in syncytiotrophoblast cells of preeclamptic placentas, which was significantly higher than that of normal placentas (p = 0.005). A mild expression of TNF-alpha in both normal and preeclamptic syncytiotrophoblasts was seen (p = 0.435). In addition, a strong expression of iNOS in normal syncytiotrophoblasts was found, but the intensity of the iNOS expression was highly reduced in preeclamptic placentas (p = 0.001). No correlation was detected between COX-2, TNF-alpha and iNOS expression levels. Conclusion: The findings of a decrease of iNOS expression and an increase of COX-2 expression in placenta suggest the existence of functional roles of iNOS and COX-2 in the pathophysiology of PE, probably by contributing to the reduced placental blood flow and increased resistance to flow in the fetomaternal circulation.