ASSESSMENT OF PLACENTAL OXIDATIVE STRESS PARAMETERS IN PREECLAMPTIC AND NORMAL PREGNANT WOMEN

Objective: Oxidative stress occurs when cellular levels of reactive oxygen species exceed antioxidant capabilities and has been implicated in thepathogenesis of pre-eclampsia. In this study, we examined the tissue levels of endogenous antioxidant enzymes or proteins (superoxide dismutase[SOD], glutathione peroxidise, reduced glutathione, catalase, and thioredoxin) and the levels of lipid peroxides, protein carbonyls, hydrogen peroxide,and nitrosative biomarkers in the placental samples from normal and pre-eclamptic pregnancies.Results: Pre-eclamptic tissue homogenates demonstrated significantly increased levels of lipid peroxidation (21.61±0.18 vs. 5.695±0.46) anda trended increase in protein carbonyls (245.95±4.05 vs. 203.48±3.65) concentration when compared to controls. The levels and activities of theantioxidant proteins; SOD (365.2±2.915 vs. 205.6±3.76), thioredoxin (100.64±3.38 vs. 80.89±3.37), glutathione peroxidase (340.88±6.16 vs.164.46±3.03), catalase (5.26±0.02 vs. 4.62±0.11), and reduced glutathione (46.99±0.508 vs. 28.19±0.178) were all found to be significantly reducedwhen comparing pre-eclamptic placental tissue homogenates to gestational age matched control placentae from non pre-eclamptic pregnancies.Conclusion: The results of this study demonstrate a decreased enzymatic antioxidant capacity and increased oxidation in placental tissue from preeclampticwomen,whichmaycontributetothe pathogenesis of this complexdisorder.Keywords: Oxidative stress, Reactive oxygen species, Superoxide dismutase, Glutathione peroxidise, Reduced glutathione, Catalase, Thioredoxin,Lipid peroxides and protein carbonyls