Fetal hemoglobin in preeclampsia: a new causative factor, a tool for prediction/diagnosis and a potential target for therapy

Abstract

Purpose of review: Preeclampsia, one of the leading causes of pregnancy complications, affects 3-7% of pregnant women. This review summarizes the present knowledge of a new potential cause of the disease and suggests a method for its prediction/diagnosis and a possible treatment, both based on the recent findings on the involvement of fetal hemoglobin (HbF) and the heme and radical scavenging protein A1M (alpha-1-microglobulin).

Recent findings: Gene and protein profiling studies have independently shown that increased amount of free HbF is accumulated in the preeclampsia placenta. As a result of a predominantly oxidative damage to the blood-placenta barrier, HbF leaks over to the maternal blood circulation. Elevated levels can be measured already in the first trimester, and later in pregnancy, the levels correlate with the blood pressure in women with preeclampsia. Ex-vivo data show that the human protein A1M, an endogeneous antioxidation protection protein, can prevent Hb-induced damage to the placenta, restore the blood-placental barrier and prevent maternal tissue damage.

Summary: Free HbF may provide both a predictive and a diagnostic clinical biomarker from the first trimester. A1M has the potential as a future pharmacological treatment for preeclampsia.