Upregulation of exofacial peroxiredoxin-thioredoxin system of lymphocytes and monocytes in preeclampsia

Objectives: An imbalanced redox homeostasis resulting in oxidative stress is present in preeclampsia. Peroxiredoxin-1 (PRDX1) and thioredoxin-1 (TRX1) regulatory enzymes are also contributing to the redox homeostasis, but were not investigated so far in preeclampsia. Thus, we have aimed to characterize PRDX1, TRX1 and oxidative stress biomarkers in blood samples of pregnant women with preeclampsia.

Study design: Twelve patients with preeclampsia (PE) were enrolled into the study. Seven third trimester healthy pregnant women (HP) were accepted as control group.

Main outcome measures: Peripheral venous blood samples of healthy and preeclamptic pregnant women were analyzed. Plasma level of advanced oxidation protein products (AOPP) was determined by spectrophotometry. The exofacial PRDX1 and TRX1 expression of lymphocytes and monocytes was detected by flow cytometry.

Results: The plasma AOPP level was significantly higher in preeclampsia compared to the healthy pregnant group. Significantly higher percentage of PRDX1 and TRX1 expressing lymphocytes and monocytes were detected in the blood samples of preeclamptic women compared to healthy pregnant controls. The ratio of circulating PRDX1 and TRX1 expressing lymphocytes and monocytes showed a significant inverse correlation with the birth weight of newborns.

Conclusions: We have revealed that the level of advanced oxidation protein products is increased and the exofacial peroxiredoxin-1 and thioredoxin-1 system in lymphocytes and monocytes is upregulated in preeclampsia. In addition, the ratio of peroxiredoxin-1 and thioredoxin-1 positive circulating lymphocytes and monocytes correlates inversely with the neonatal birth weight, which finding indicates that pregnancies complicated by intrauterine growth restriction are accompanied by a higher level of oxidative stress.