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

Goksu Erol A. Y., Nazli M., Elis Yildiz S.

The journal of maternal-fetal & neonatal medicine : the official journal of the European Association of Perinatal Medicine, the Federation of Asia and Oceania Perinatal Societies, the International Society of Perinatal Obstetricians, cilt.25, sa.6, ss.826-30, 2012 (SCI-Expanded, Scopus)

Özet

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-α (TNF-α) 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-α 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-α 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-α 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. © 2012 Informa UK, Ltd.

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-α (TNF-α) 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-α 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-α 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-α 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.