Concentrations of homocysteine, related metabolites and asymmetric dimethylarginine in preeclamptic women with poor nutritional status

Abstract

Background: Hyperhomocysteinemia, a proxy measure for the nutritional status of the B vitamins, may be involved in the etiology of preeclampsia via inducing endothelial dysfunction. Asymmetric dimethylarginine (ADMA) is an inhibitor of NO-synthase that may adversely affect the endothelium.

Materials and methods: We investigated serum concentrations of folate, vitamin B12, B6, homocysteine (Hcy) and related metabolites in 139 Syrian preeclamptic women and 93 asymptomatic pregnant women of comparable age, gestational age and socioeconomic status. Plasma concentrations of ADMA were determined in a subset of age- and gestation-age-matched pairs of patients and controls (n=63).

Results: Higher concentrations of Hcy, cystathionine and methylmalonic acid (MMA) were closely linked to a lower status of the B vitamins. Higher concentrations of Hcy and cystathionine were observed in the preeclamptic group than in the matched controls (median Hcy 9.3 vs. 6.0 micromol/L; median cystathionine 284 vs. 232 nmol/L). Serum folate was significantly lower in patients than in controls (16.4 vs. 36.0 nmol/L). Folate supplementation was less likely to be used in preeclamptic women. Concentrations of MMA were elevated in patients and controls and did not differ significantly between the two groups. Median plasma concentrations of ADMA were significantly lower in asymptomatic women than in those who developed preeclampsia before the 37th week of gestation (0.61 vs. 0.68 micromol/L).

Conclusions: Elevated serum concentrations of Hcy, cystathionine and MMA indicate poor status of the B vitamins during pregnancy. The adverse effect of Hcy on endothelial function might be related to ADMA in early-onset preeclampsia. More emphasis should be placed on increasing the intake of B vitamins in pregnant women from developing countries.