Oxidative stress markers and thrombomodulin plasma levels in women with early and late severe preeclampsia.

BACKGROUND: Preeclampsia (PE) is a pregnancy disease associated with oxidative stress and endothelial dysfunction. It can be classified according to the severity and onset-time of clinical symptoms (early PE:<34 weeks, late PE:≥34 weeks). METHODS: We evaluated markers of oxidative stress (thiobarbituric acid reactive substances-TBARs and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide)-MTT) and endothelial lesion (thrombomodulin-TM) in early (N = 24) and late severe PE(N = 22) and normotensive pregnant women(N = 26). RESULTS: MTT levels were higher in early sPE than in normotensive pregnancy (P = 0.03). No difference was found comparing late sPE versus normotensive pregnancy, and early sPE versus late sPE. TM levels were higher in early sPE comparing to late sPE women (P = 0.05), but no difference was found between early or late sPE versus normotensive groups. TBARs levels did not differ significantly among the three groups. These data suggest that endothelial lesion and the antioxidant status are more pronounced in early sPE. Moreover, lipid peroxidation might be an early event in PE, stimulating a compensatory antioxidant defense later in pregnancy. CONCLUSIONS: Longitudinal studies involving pregnant women with risk factors for PE development and including other methods for oxidative stress and endothelial lesion determination should be conducted in order to better evaluate the role of these processes in PE pathogenesis.