Plasma concentrations of sAxl are associated with severe preeclampsia

Preeclampsia, a multisystem disorder unique to pregnancy, is a major cause of maternal and perinatal mortality and morbidity. Inadequate trophoblast invasion and vascular dysfunction are believed to be involved in preeclampsia. Axl, which interacts with its ligand Gas6, known to regulate cell migration, adhesion, and vascular angiogenesis or homeostasis and vascular network formation, may be implicated in preeclampsia, as preeclampsia is a specific vascular disease. sAxl, a soluble form of Axl, is bound to Gas6 in plasma, which inhibits the activation of the Axl-Gas6 pathway. The aim of this study was to determine the changes and significance of plasma concentrations of sAxl in severe preeclampsia, as well as its correlation with the clinical parameters of severe preeclampsia.

Fifty-eight women with severe preeclampsia and 31 healthy pregnant women were included in the study, from April 2012 to October 2012. Plasma sAxl concentrations were detected with an immunosorbent assay (ELISA) kit.

Plasma sAxl concentrations were significantly higher in the preeclampsia group (61.52±17.57ng/mL) than in the normal pregnancy group (45.29±15.44ng/mL) (P<0.05). Plasma sAxl concentrations in the severe preeclampsia patients correlated positively with systolic and diastolic blood pressures (r=0.628, P<0.05 vs. r=0.394, P<0.05, respectively) and proteinuria (r=0.583, P<0.05), but inversely with plasma albumin (r=-0.444, P<0.05), gestation of delivery (r=-0.554, P<0.05), and birth weight (r=-0.476, P<0.05). Multiple linear regression analysis indicated that systolic blood pressure and proteinuria were influence factors of plasma sAxl levels (β1=0.520, P<0.05; β2=0.461, P<0.05).

Plasma sAxl concentrations were higher in the preeclampsia patients, and plasma sAxl levels were correlated with the clinical parameters of severe preeclampsia. Furthermore, systolic blood pressure and proteinuria might be influence factors of plasma sAxl level.