New scope in angiogenesis: Role of vascular endothelial growth factor (VEGF), NO, lipid peroxidation, and vitamin E in the pathophysiology of pre-eclampsia among Egyptian females

Objectives: The purpose of this study was to investigate the role of VEGF, NO, MDA, and Vitamin E in the pathophysiology of preeclampsia (PE) among Egyptian women. Patients and Methods: Our study included 20 pregnant women with mild PE, 40 pregnant women with severe PE, 20 normal control women and 20 normal control pregnant women. Plasma from all women were subjected to estimation of VEGF using ELISA kit, estimation of nitrates (as end product of NO) and MDA by chemical methods and measurement of Vitamin E using HPLC. Results: The obtained data from this study revealed that, VEGF may be used as a useful marker for PE which is elevated in plasma of women with PE (mild and severe) compared to controls. VEGF could differentiate between PE and controls at a cut-off value of: 70 ng/mL with a sensitivity of 95% and a specificity of 90%. Moreover, at a cut-off value of 250 ng/mL, VEGF could discriminate mild PE from severe PE with a sensitivity of 77.5% and a specificity of 85%. With respect to nitrate levels, they were significantly elevated in normal pregnant women compared with normal controls. Meanwhile, nitrate levels showed a highly significant decrease in PE in relation to both controls, explaining the vasoconstriction and high blood pressure occurring in preeclamptic women. Correlation analysis revealed significant inverse correlation between nitrate levels and VEGF. Lipid peroxidation as indicated by MDA was enhanced in preeclamptic women as compared to healthy controls. The increase in MDA levels was correlated to the severity of PE. A highly significant fall in vitamin E as an antioxidant-scavenging vitamin was seen in preeclamptic women as compared to the controls. Also, a significant drop in the vitamin level was found in severe PE in comparison to mild PE. The oxidant/antioxidant correlation was illustrated by the inverse correlation between vitamin E and MDA(r = -0.837, p = 0.000). Conclusion: The findings from this study indicated that VEGF may be used as a clinically useful biomarker for PE for better diagnosis, to differentiate between mild and severe PE, and may also be a target for therapeutic intervention of PE. The increase in levels of VEGF together with reduction in NO levels could confirm the existence of vascular reactivity and endothelial disturbance in PE. The decrease in the vasodilator, NO may in part lead to the vasospasm of preeclampsia, which consequently produces hypoxia. The latter may be a cause of an elevation of VEGF (angiogenic factor) levels in PE. Meanwhile, elevated levels of lipid peroxides together with impaired antioxidant defense mechanisms may play a role in the etiology of PE. (C) 2001 The Canadian Society of Clinical Chemists. All rights reserved.