142: Hyperglycemia Impedes First Trimester Extravillous Cytotrophoblast Function Via Apoptotic Signaling

Preeclampsia (preE) is a syndrome of hypertension and proteinuria in pregnancy with multiple pathophysiologic triggers. Approximately 20% of the diabetic pregnant women develop preE. Although the pathogenesis of preE is unknown, many investigations focused on the incompleteness of placental invasion of cytotrophoblast cells (CTBs). In a recent study, we have shown that hyperglycemia impairs CTBs function via stress signaling. In the present study, we assess the apoptotic signaling in excess glucose-induced CTBs. Human extravillous CTBs (Sw. 71) were treated with 100, 200, 300 or 400 mg/dL glucose for 48h. Some cells were pretreated with a p38 inhibitor (SB203580) or a peroxisome proliferator-activated receptor gamma (PPARγ) ligand (rosiglitazone).While other cells were treated with D-Mannitol to evaluate the osmotic effect. Thereafter, cell lysates were utilized to measure PPARγ expression, p38 MAPK phosphorylation, and apoptotic and stress signaling proteins; Bcl-2-associated X protein (Bax), anti-apoptotic Bcl-2 and caspase-3 and 9 and pro-inflammatory cyclooxygenase-2 (Cox-2) expression by western blot. Statistical comparisons were performed using analysis of variance with Duncan’s post hoc test. Both p38 MAPK phosphorylation and PPARγ expression were upregulated (p<0.05) in CTBs treated with ≥150 mg/dL glucose compared to basal (100 mg/dL). The expression of Bax/Bcl-2, Cox-2, caspase-3 and 9 were up-regulated (p<0.05) in CTBs treated with ≥150 mg/dL glucose compared to basal. The SB203580 or rosiglitazone pretreatment showed an attenuation of hyperglycemia-induced apoptotic signaling. D-Mannitol had no effect on the expression of apoptotic signaling in CTBs. Hyperglycemia induced the apoptotic signaling in CTBs by upregulating the Bax/Bcl2, caspase-3 and 9 and Cox-2 expression. The attenuation of hyperglycemia-induced upregulation of apoptotic signaling by SB203580 or rosiglitazone pretreatment suggests the involvement of apoptotic signaling in CTBs dysfunction.