Leukocyte Selenium, Zinc, and Copper Concentrations in Preeclamptic and Normotensive Pregnant Women

Abstract

Preeclampsia is an important cause of maternal and perinatal mortality worldwide. The etiology of this relatively common medical complication of pregnancy, however, remains unknown. We studied the relationship between maternal leukocyte selenium, zinc, and copper concentrations and the risk of preeclampsia in a large hospital-based case-control study. One hundred seventy-one women with proteinuric pregnancy-induced hypertension (with or without seizures) comprised the case group. Controls were 184 normotensive pregnant women. Leukocytes were separated from blood samples collected during the patients' postpartum labor and delivery admission. Leukocyte concentrations for the three cations were measured by inductively coupled plasma-mass spectrometry (ICP-MS). Concentrations for each cation were reported as micrograms per gram of total protein. Women with preeclampsia had significantly higher median leukocyte selenium concentrations than normotensive controls (3.23 vs 2.80 microg/g total protein, p < 0.0001). Median leukocyte zinc concentrations were 31% higher in preeclamptics as compared with controls (179.15 vs 136.44 microg/g total protein, p < 0.0001). Although median leukocyte copper concentrations were slightly higher for cases than controls, this difference did not reach statistical significance (17.72 vs 17.00 microg/g total protein, p = 0.468). There was evidence of a linear increase in risk of preeclampsia with increasing concentrations of selenium and zinc. The relative risk for preeclampsia was 3.38 (adjusted odds ratio [OR] = 3.38, 95% confidence interval [CI] = 1.53-7.54) among women in the highest quartile of the control selenium distribution compared with women in the lowest quartile. The corresponding relative risk and 95% CI for preeclampsia was 5.30 (2.45-11.44) for women in the highest quartile of the control zinc distribution compared with women in the lowest quartile. There was no clear pattern of a linear trend in risk with increasing concentration of leukocyte copper concentrations (adjusted for linear trend in risk = 0.299). Our results are consistent with some previous reports. Prospective studies are needed to determine whether observed alterations in selenium and zinc concentrations precede preeclampsia or whether the differences may be attributed to preeclampsia-related alterations in maternal and fetal-placental trace metal metabolism.

The Role of Calcium, Magnesium, and Zinc in Pre-Eclampsia

“…Despite a large list of theories put forward to explain the etio-pathogenesis of pre-eclampsia, the exact nature of the etiological factors is not known [4,5,27]. Recently, the emphasis has been laid on the role of dietary factors in pathogenesis of pre-eclampsia [2,9].…”

Catalase Activity, Serum Trace Element and Heavy Metal Concentrations, and Vitamin A, D and E Levels in Pre-Eclampsia

“…16 For Cu as with Zn, there is however considerable inconsistency in results concerning the relationship between maternal plasma concentrations and pre-eclampsia. 16,17 Some metals are essential to maintain the human body's metabolism, but they can lead to poisoning as a result of bioaccumulation. 18 Lead (Pb) and cadmium (Cd) increase oxidative stress, 19 The inclusion criteria for entry into the study were: normal blood pressure during the first 20 weeks of gestation (for PE women); no previous history of metabolic disorders, renal disease, chronic hypertension or diabetes mellitus; and no history of antioxidant, antihypertensive medication, or aspirin intake.…”

Monitoring the Copper Content of Serum and Urine in Pregnancies Complicated by Preeclampsia

“…Preeclampsia is associated with an imbalance of increased lipid peroxides and decreased antioxidants [4,10]. Ceruloplasmin acts as an antioxidant by several mechanisms: (1) inhibiting iron-dependent lipid peroxidation (LP) and HO formation from H2O2 via its ferroxidase activity, (2) reacting with and scavenging H2O2 and superoxide anion, and (3) inhibiting Cu-induced LP by binding Cu ions [10].…”

“…Cu, a component of several metalloenzymes and an essential cofactor for the antioxidant enzyme superoxide dismutase, is known to affect the level of norepinephrine and dopamine in the brain [3]. Excessive lipid peroxidation or oxidative stress is considered to be an important determinate of diffuse endothelial dysfunction and preeclampsia [4]. Trace metals, because of their biological role as catalysts for endogenous antioxidant enzymes, have been the subject of clinical research designed to assess the etiology of preeclampsia [5,6].…”