Abstract
Oxidative stress is associated with several diseases including reproductive disorders and preeclampsia. Defence against oxidative stress is provided by numerous exogenous antioxidants (e.g. vitamins E and C) or endogenous enzyme systems (e.g. catalase and glutathione-related enzymes). When during pregnancy the maternal antioxidant capacity is insufficient to deal with the increased load of oxidative compounds, preeclampsia or the hemolysis, elevated liver enzymes and low platelets syndrome may occur. In this thesis several studies on glutathione and glutathione-related enzymes on male fertility, embryonic, foetal and placental development are presented). In addition, studies on the redox-balance of glutathione and other thiols in preeclampsia, and genetic polymorphisms in association with to oxidative stress in preeclampsia are described. From this thesis it may conclude that glutathione and related enzymes are correlated with male fertility, are important for normotensive pregnancy, whereas disturbances are seen in preeclampsia and the HELLP syndrome. Disturbances of thiol levels are associated with preeclampsia. Using the free-to-oxidised ratio of thiols we were able to demonstrate the presence of a transient oxidative stress during pregnancy, being even more pronounced in preeclampsia, disappearing after delivery. However, in women with severe preeclampsia a lower free-to-oxidised ratio for homocysteine is found after consecutive pregnancies, following their index-pregnancy. Therefore, the free-to-oxidised ratio for homocysteine may be a predictor for preeclampsia or may serve as indicator for the development of cardiovascular problems in later life. Oxidative stress during preeclampsia seems not to be associated with polymorphisms in the genes encoding for the p22phox subunit NAD(P)H oxidase or haptoglobin. However, as an angiogenic factor, haptoglobin may play a role during placental development
