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
Em. El-salahy et al., 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, CLIN BIOCH, 34(4), 2001, pp. 323-329
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 Eg
yptian 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 contr
ol pregnant women. Plasma from all women were subjected to estimation of VE
GF using ELISA kit, estimation of nitrates (as end product of NO) and MDA b
y 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 (mil
d 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 s
pecificity of 90%. Moreover, at a cut-off value of 250 ng/mL, VEGF could di
scriminate mild PE from severe PE with a sensitivity of 77.5% and a specifi
city of 85%. With respect to nitrate levels, they were significantly elevat
ed in normal pregnant women compared with normal controls. Meanwhile, nitra
te levels showed a highly significant decrease in PE in relation to both co
ntrols, explaining the vasoconstriction and high blood pressure occurring i
n preeclamptic women. Correlation analysis revealed significant inverse cor
relation between nitrate levels and VEGF. Lipid peroxidation as indicated b
y MDA was enhanced in preeclamptic women as compared to healthy controls. T
he increase in MDA levels was correlated to the severity of PE. A highly si
gnificant fall in vitamin E as an antioxidant-scavenging vitamin was seen i
n 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 o
xidant/antioxidant correlation was illustrated by the inverse correlation b
etween 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 differentiat
e between mild and severe PE, and may also be a target for therapeutic inte
rvention of PE. The increase in levels of VEGF together with reduction in N
O 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 la
tter may be a cause of an elevation of VEGF (angiogenic factor) levels in P
E. Meanwhile, elevated levels of lipid peroxides together with impaired ant
ioxidant defense mechanisms may play a role in the etiology of PE. (C) 2001
The Canadian Society of Clinical Chemists. All rights reserved.