Prenatal ethanol exposure and placental hCG and IGF2 expression

Fetal alcohol spectrum disorder (FASD) is the main cause of preventable non-genetic mental retardation. Diagnosis of prenatal exposure to ethanol (PEE) is based on questionnaires and biomarkers in perinatal matrices. Early diagnosis of FASD is important to mitigate secondary disabilities that will arise later in life. It is important to identify biomarkers related to cellular damage caused by PEE. The main objective was to identify novel candidate biomarkers from placental tissue using an in vitro model of exposure to ethanol and to support it in placental tissue obtained from pregnancies with PEE assessed by fatty acid esters in meconium samples.

First, hormone production was examined using two different human trophoblast cell lines, JEG3 and BeWo. Viable cell count by exclusion method was analyzed and human chorionic gonadotrophin (hCG) and insulin-like growth factor 2 (IGF2) were quantified by Western blot and ELISA. Second, these techniques were used in protein lysates from human placentas from pregnancies with and without exposure to ethanol.

Both trophoblast cell lines showed a decrease in cell viability accompanied with apoptosis activation after a chronic ethanol treatment. Moreover, we showed an increase in the secretion of hCG and IGF2 in a dose-dependent manner. Interestingly, this increase was also observed in a set of human placenta tissue from fetuses exposed prenatally to ethanol.

Ethanol exposure during pregnancy causes placenta cell damage, so altering its normal function. The specific hCG and IGF2 release pattern is a candidate surrogated biomarker of the damage due to PEE.