Homocysteine and Cellular Fibronectin are Increased in Preeclampsia,not Transient Hypertension of Pregnancy

Objective. The objective of this study was to confirm that endothelial dysfunction is present in preeclampsia and absent in transient hypertension of pregnancy, and to determine whether the cardiovascular risk factor homocysteine is associated with the degree of endothelial dysfunction.

Methods. We measured cellular fibronectin (as a marker of endothelial injury) and total plasma homocysteine in samples collected at the time of admittance to labor and delivery in 17 women with preeclampsia (increased blood pressure, proteinuria, and hyperuricemia), 16 women with transient hypertension of pregnancy (only increased blood pressure), and 34 normal pregnant women. Each subject with preeclampsia was matched by prepregnancy body mass index, race, and gestational age at delivery to one subject with transient hypertension of pregnancy and two controls.

Results. Cellular fibronectin was found to be significantly increased in women with preeclampsia compared to subjects with transient hypertension of pregnancy or normal pregnant women (22.9±14.1 μg/mL versus 10.9±5.4 and 10.1±6.2 μg/mL, respectively, p<0.0001). Similarly, total plasma homocysteine was also significantly increased in the women with preeclampsia compared to subjects with transient hypertension of pregnancy or normal pregnant women (8.3±2.5 μM versus 5.5±2.2 and 5.4±3.4 μM respectively, p<0.01). However, contrary to our hypothesis, there was no apparent association between cellular fibronectin and homocysteine.

Conclusions. The increased concentrations of homocysteine observed in preeclampsia are not a general feature of all hypertensive complications of pregnancy. Furthermore, endothelial dysfunction is present in preeclampsia and is not evident in transient hypertension of pregnancy. However, the apparent endothelial dysfunction in preeclampsia is not explained by the increase in homocysteine concentrations observed.