Comparison of selenium levels in pre-eclamptic and normal pregnancies

Abstract

Abnormal placentation is the likely cause of the slow fetal growth and the high levels of circulating lipid peroxides found in severe pre-eclampsia. These peroxides are probably responsible for the high thromboxane:prostacyclin ratio found in this disease and may participate in the endothelial cell damage which is its most notable feature. Selenium (Se), because of its role in glutathione peroxidase, is suggested to be an important component of the removal system for these damaging peroxides. Serum-Se concentrations have therefore been measured in 19 pairs of pre-eclamptic women and matched controls. Infant birth-weights were recorded. No significant difference was found in the concentrations of Se in pre-eclamptic and control groups. Serum Se was found to be low in both groups. Birthweights were significantly lower in the pre-eclamptic group. The interpretation of serum-Se measurements from the third trimester of a pre-eclamptic pregnancy is complicated by the reduced fetal growth and probable lower Se take-up by the fetus in such a pregnancy. The merits of alternative measurements, such as total intravascular Se, placental Se, or samples from an earlier stage of gestation, are discussed. The importance of factors other than Se to the activity of glutathione peroxidase, and of other antioxidants to pre-eclamptic, is stressed.

Low selenium status is associated with the occurrence of the pregnancy disease preeclampsia in women from the United Kingdom

“…13 Thus toenail selenium concentrations in this study are similar to those measured in women in the Netherlands [0.575±0.109 mg/kg (mean±SD)] 16 but considerably lower than those in US women [0.83±0.16 -0.92±0.15 mg/kg (mean±SD)]. 17 The relatively low selenium status observed in this group is consistent with our previous finding of low selenium status in normal obstetric patients, of average gestation 33 weeks, attending the same hospital (median plasma selenium 48.5 µg/l, range 23.1-101.4) 21 and the lower selenium status found in most parts of Europe when compared to North America. 13 A repeat of our study in an area of higher selenium status (e.g.…”

“…13 (The balance of these two eicosanoids favours blood-clotting in preeclampsia. 21 ) Overall, the effect of the GPxs is to reduce the activity of the cyclooxygenases and lipoxygenases which require a minimum peroxide tone to be optimally active, thus they limit the production of inflammatory and pro-agreggatory prostaglandins and leukotrienes. 13 Furthermore GPx rapidly reduces peroxynitrite to harmless products.…”

“…This situation may be exacerbated by the expansion in plasma volume and reduced plasma selenium concentration normally associated with pregnancy. 21 Implications. Given the serious nature of preeclampsia and the potentially adverse consequences of premature delivery and the associated low birthweight, our results may have important public-health implications, particularly in the light of the reduction in selenium intake and status, both in the UK and in a number of other European countries, over the last 20 to 25 years.…”

Blood selenium and glutathione peroxidases in miscarriage

“…In another study Rayman et al 23 have shown that in the serum of pregnant women (mean, 33 weeks of pregnancy) the median selenium level was only 48.5 ng/ mL. In our present study plasma selenium levels in normal pregnancy (mean, 11.8 weeks of pregnancy) were 54.6 ng/ mL, which did not differ from the levels of aborted women (56.0 ng/mL), but were signi®cantly lower compared with non-pregnant controls (66.1 ng/mL).…”

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“…21 ) Overall, the effect of the GPxs is to reduce the activity of the cyclooxygenases and lipoxygenases which require a minimum peroxide tone to be optimally active, thus they limit the production of inflammatory and pro-agreggatory prostaglandins and leukotrienes. 13 Furthermore GPx rapidly reduces peroxynitrite to harmless products.…”