Biomarkers of placental redox imbalance in pregnancies with preeclampsia and consequent perinatal outcomes

Objective To compare redox and inflammatory markers between normal and PE-derived placentas and to evaluate the relationship between placental redox imbalance markers and perinatal outcomes in pregnancies with PE. Methods This was a cross-sectional study conducted at the maternity hospital of a university hospital in Maceio-Alagoas, Brazil, in 2017, including women diagnosed with PE and healthy pregnant women and their conceptuses. After screening, standardized questionnaires containing socioeconomic, clinical, obstetric and anthropometric data were applied. After delivery, placental samples were collected for quantification of biomarkers of redox imbalance (catalase – CAT; malondialdehyde – MDA; hydrogen peroxide – H2O2; superoxide dismutase – SOD; reduced glutathione – GSH; oxidized glutathione – GSSG; and their ratio – GSH/GSSG) and inflammation (myeloperoxidase – MPO; interleukin (IL)-6; IL-8; IL-10; and tumor necrosis factor-alpha – TNF-α). All biomarkers were evaluated via linear regression with adjustments of variables with measures of weight, length, head circumference (HC), chest circumference (CC) and gestational age of newborns at birth, considering p Results A total of 100 pregnant women with PE and 50 healthy pregnant women were studied. Higher placental levels of catalase (p = 0.018), SOD (p = 0.031), the GSH/GSSG ratio (p = 0.019) and IL-6 (p = 0.010) and lower GSSG (p = 0.001) were observed in pregnant women with PE than in the control group. Positive associations between placental GSH levels and body weight, HC, CC and gestational age at birth (p Conclusion PE-derived placentas had high concentrations of some antioxidants (enzymes and thiols), which might be a compensation mechanism against oxidative stress. Placental GSH levels were the only biomarker, among the studied ones, related positively with beneficial perinatal outcomes, suggesting that this endogenous antioxidant plays an important role in maintaining the health of the conceptus and women with PE.