F2α-isoprostane, Na+-K+ ATPase and membrane fluidity of placental syncytiotrophoblast cell in preeclamptic women with vitamin E supplementation.

Background: The aim of our study was to analyze F2α-isoprostane level, Na+-K+ ATPase activity and placental syncytiotrophoblast cell membrane fluidity in preeclamptic women who received vitamin E supplementation. Methods: The study was conducted between September 2003 and February 2005 at Budi Kemuliaan Maternity Hospital, Central Jakarta. Samples were 6 preeclamptic women with vitamin E supplementation, 6 preeclamptic women without vitamin E supplementation and 6 normal pregnant women. The dose of vitamin E was 200 mg daily. F2α-isoprostane was measured with ELISA reader at λ of 450 nm. Cell membrane fluidity was measured by comparing the molar ratio of total cholesterol and cell membrane phospholipid concentration. The cholesterol was measured by Modular C800 using Roche reagent. Phospholipid was measured by Shimadzu RF5301PC spectrofluorometer (excitation 267 nm, emission 307 nm). Na+-K+ ATPase activity was inhibited by ouabain. Pi production was measured with Fiske and Subbarow method using spectrophotometer at λ of 660 nm. Data was analyzed using F test with one-way ANOVA. Results: Vitamin E supplementation in preeclamptic women decreased the oxidative stress, indicated by significantly lower level of F2α-isoprostane compared to those without vitamin E (26.72 ± 11.21 vs 41.85 ± 7.09 ng/mL, respectively, p = 0.017). Membrane fluidity in syncytiotrophoblast cell of preeclampsia with vitamin E group was maintained at 0.39 ± 0.08 while in those without vitamin E was 0.53 ± 0.14 (p = 0.04). Na+-K+ ATPase activity in syncytiotrophoblast cell membrane was not affected by vitamin E (p = 0.915). Conclusion: Vitamin E supplementation in preeclamptic women decreases F2α-isoprostane level and maintains cell membrane fluidity of syncytiotrophoblast cells; however, it does not increase Na+-K+ ATPase enzyme activity.

Does VEGF concentration in pre-eclamptic serum induce sVCAM-1 production in endothelial cell culture.

Serum concentrations of VEGF (Vascular Endothelial Growth Factor) are elevated in preeclampsia. In addition to inducing mitosis and increase permeability of endothelial cells, VEGF was reported to activate endothelial cells to produce cell adhesion molecules. Cell adhesion molecules play an important role in the inflammation process by inducing adherence of leukocytes in blood stream to the endothelial cells. The aim of this study is to investigate the effect of VEGF in serum from preeclamptic patients on sVCAM-1 (soluble vascular adhesion molecules-1) production in endothelial cell culture. Twelve sera from women with preeclampsia and 11 from women with normal pregnancy (controls) in 20% concentration were added to human umbilical vein endothelial cell culture (HUVEC) and incubated for 24 hours. All subjects have agreed to participate in this study and signed the informed consent form. sVCAM-1 concentration in the supernatant was measured by ELISA. VEGF concentration tends to be higher in preeclamptic serum than control, but the difference is not stastitically significant. The production of sVCAM-1 by endothelial cells exposed to preeclamptic serum was significantly higher than the production by endothelial cells exposed to serum from control (p<0.05). No correlation was found between the difference in VEGF concentrations in preeclamptic and control sera, and sVCAM-1 production by endothelial cell culture.