Effects of Selenium Supplementation on Soluble FMS-Like Tyrosine Kinase-1 and Glutathione Peroxidase Levels and the Plasminogen Activator Inhibitor-1: Plasminogen Activator Inhibitor-2 Ratio in Pregnant Women

Abstract

Background: Preeclampsia is a hypertensive disorder of pregnancy, which is associated with increased maternal and prenatal morbidity and mortality. Oxidative stress associated with preeclampsia may be a consequence of reduced antioxidant defense pathways that might involve inadequate glutathione peroxidase (GPx) levels, perhaps linked to reduced selenium availability. The soluble FMS-like tyrosine kinase-1 (sFlt-1) that contributes to endothelial dysfunction may be partially responsible for the clinical manifestation of preeclampsia. Furthermore, elevated plasminogen activator inhibitor-1 (PAI-1) and decreased plasminogen activator inhibitor-2 (PAI-2) are found in preeclamptic women. Hence, the PAI1: PAI2 ratio maybe a predictor of preeclampsia. Objectives: The objective of this study was to evaluate the effects of selenium supplementation on sFlt-1, GPx activity and PAI1: PAI2 ratio in pregnant women. Materials and Methods: A total of 125 high-risk pregnant women (with a familial history of hypertension, hyperlipidemia and other risk factors for preeclampsia) in the first trimesters of pregnancy were assigned to either selenium (n = 61) or placebo (n = 64) groups. The selenium group received 100 μg/day of selenium as a selenium-yeast tablet for six months. The placebo group received a placebo yeast tablet for the same period. At the beginning of the trial and at the end, blood samples were collected and the levels of sFlt-1, PAI-1, PAI2 and GPx were measured in blood serum and plasma. Results: Serum selenium concentrations were raised in the selenium group (P < 0.001) from the first to the third trimester, but was unchanged in the placebo group (P = 0.85). The results showed that sFlt-1 had significantly increased in both groups by the end of the gestation period, and selenium supplementation had no significant effect on the selenium group (P = 0.51). However, GPx activity was significantly increased in the selenium treatment group after supplementation compared to the control group (P < 0.001). The PAI1: PAI2 ratio was not significantly different between the two groups (P = 0.44). Conclusions: Selenium intake during the second and third trimester of pregnancy increased GPx activity but did not have a significant effect on serum sFlt-1 levels or the ratio of PAI1: PAI2 in the serum.