Low Serum Levels of ABCA1, an ATP-Binding Cassette Transporter, Are Predictive of Preeclampsia.

Preeclampsia is a pregnancy-specific disorder characterized by hypertension and proteinuria, but the exact cause of preeclamptic hypertension remains unknown. ATP-binding cassette subfamily A member 1 (ABCA1) reverses cholesterol transport and eliminates excess cholesterol from tissues, whereas higher levels of cholesterol may lead to hypertension. Thus, ABCA1 affects the blood lipid profile. We have hypothesized that serum ABCA1 levels may influence the onset of hypertension and increase the risk of preeclampsia. To test this hypothesis, we measured serum ABCA1 levels in 50 normal pregnancies, 36 preeclamptic pregnancies, and 24 small-for-gestational-age (SGA) pregnancies during three trimesters. We also measured the concentrations of serum ABCA1 in non-pregnant women (n = 60), showing its normal ranges of 0.16 to 0.52 ng/ml. Importantly, the serum levels of ABCA1 were similar among non-pregnant women, normal pregnancies and SGA pregnancies. In contrast, the serum ABCA1 levels were significantly lower in preeclamptic pregnancies (0.06 ± 0.03 ng/ml) than those in non-pregnant women, and normal and SGA pregnancies (P < 0.05). Low serum ABCA1 levels were associated with the increases in the concentrations of blood lipid (low density lipoprotein cholesterol, total cholesterol and triglycerides) and with the decrease in the concentration of high-density lipoprotein cholesterol (P < 0.01), all of which may contribute to the onset of hypertension and eventually preeclampsia. Moreover, the preeclamptic pregnancy was diagnosed with high sensitivity from the nulliparous pregnancies if the cutoff value for serum ABCA1 was 0.06 ng/ml. Thus, low serum levels of ABCA1 are predictive of preeclampsia.