ABSTRACT
OBJECTIVE: To test the hypothesis that very low birth infants born to mothers with preeclampsia have higher blood pressure over the first week of life than infants whose mothers did not have preeclampsia. METHOD: Infants born at<1,350 g who survived at least one week were stratified by gestational age (
Subject(s)
Hypertension/etiology , Infant, Very Low Birth Weight , Pre-Eclampsia/physiopathology , Pregnancy Complications, Cardiovascular/physiopathology , Analysis of Variance , Anthropometry , Chi-Square Distribution , Female , Gestational Age , Humans , Infant, Newborn , Logistic Models , Pregnancy , Pregnancy OutcomeABSTRACT
Chorioamnionitis is a common cause of premature birth and is associated with significant morbidity and mortality in the mother and infant. Preterm birth shares similarities with rejection of the fetal allograft, which is characterized by increased apoptosis of placental trophoblasts. We hypothesized that there is increased trophoblast apoptosis in chorioamnionitis and that this increased apoptosis is mediated by the Fas ligand (FasL)/Fas pathway. To test our hypothesis, we examined placental villous tissues from patients with chorioamnionitis and used the TUNEL assay to demonstrate enhanced trophoblast apoptosis in patients with chorioamnionitis. When the same samples were stained for Fas, there was increased trophoblast Fas expression in patients with chorioamnionitis. To define the mechanisms responsible for this increase in trophoblast apoptosis, we cultured villous explants from uncomplicated term placentas with proinflammatory cytokines and demonstrated a marked increase in trophoblast apoptosis. By blocking FasL, we reduced tumor necrosis factor alpha-induced and interferon gamma-induced apoptosis. These data suggest that chorioamnionitis is associated with increased trophoblast apoptosis and enhanced trophoblast Fas expression. As a complement to our in vivo study, we demonstrated that cytokine-induced trophoblast apoptosis is mediated in part by the FasL/Fas pathway, suggesting that cytokines promote sensitivity to Fas-mediated apoptosis. These mechanisms may be important in perpetuating inflammation in the placental microenvironment and may contribute to the pathogenesis of chorioamnionitis.