Erythrocyte glutathione balance and membrane stability during preeclampsia

Abstract

This study aimed to determine whether oxidative damage to the erythrocyte occurs in preeclampsia, and relates to disease severity. The oxidative status of intact erythrocytes from preeclamptic patients and normal pregnant women was determined using spin echo 1H-NMR, which measures both the concentration and redox state of intracellular glutathione. Previous studies of preeclampsia have only measured total glutathione levels. Membrane fragility was determined from the degree of lysis caused by incubation in hypotonic saline. Erythrocytes from moderate-severe preeclamptic patients underwent more lysis than erythrocytes from control pregnant women (p < .05) or mild preeclamptic patients. It is suggested that increased lysis results from oxidative damage to the erythrocyte membrane, causing a decrease in membrane fluidity and reducing its ability to withstand osmotic changes. Intracellular glutathione was more oxidized in erythrocytes from pregnant women compared to nonpregnant controls (p < .05), and there was a less significant trend toward more oxidized glutathione with increasing severity of preeclampsia. The moderate-severe group showed a clear division in glutathione redox status: some patients had very oxidized glutathione while others had a normal redox balance. This novel finding suggests that some patients may be unusually susceptible to erythrocyte glutathione oxidation, possibly leading to general cellular damage, in particular HELLP Syndrome.