Preeclampsia is associated with increased susceptibility of serum lipids to copper-induced peroxidation in vitro

Background. Several reports suggest preeclampsia to be associated with oxidative stress. In view of potential experimental artifacts in these studies, we tested the effect of preeclampsia on the oxidizibility of maternal serum lipids, using an optimized ex vivo method. Methods. This prospective study included 28 pregnant women with preeclampsia and 28 women matched for maternal and gestational age with normal pregnancies. Venous blood was drawn from the consenting women. Serum levels of lipid peroxidation products and the kinetics of copper-induced oxidation ex vivo were monitored spectroscopically by continuous recording of absorbance at 245 nm. Results. The initial optical density (OD) at 245 nm, attributed to preformed products of lipid peroxidation, was higher in the women with preeclampsia than in the controls (1.26 +/- 0.02 vs. 1.17 +/- 0.02 OD units; p = 0.01). The lag phase preceding oxidation, reflecting resistance of serum lipids to oxidation, was significantly shorter in the preeclampsia group than in the controls (47.4 +/- 2.3 vs. 57.6 +/- 4.0 min; p = 0.027). Conclusions. High levels of serum hydroperoxides and increased susceptibility of serum lipids to copper-induced peroxidation ex vivo indicate preeclampsia to be associated with high oxidative stress. The role of this high oxidizibility in the pathogenesis of preeclampsia has yet to be evaluated.