Hyperglycemia in Pregnancy-Associated Oxidative Stress Augments Altered Placental Glucose Transporter 1 Trafficking via AMPK alpha/p38MAPK Signaling Cascade

GLUT1, being a ubiquitous transporter isoform, is considered primarily responsible for glucose uptake during glycolysis. However, there is still uncertainty about the regulatory mechanisms of GLUT1 in hyperglycemia in pregnancy (HIP, PGDM, and GDM) accompanied by abnormal oxidative stress responses. In the present study, it was observed that the glycolysis was enhanced in GDM and PGDM pregnancies. In line with this, the antioxidant system was disturbed and GLUT1 expression was increased due to diabetes impairment in both placental tissues and in vitro BeWo cells. GLUT1 responded to high glucose stimulation through p38MAPK in an AMPK alpha-dependent manner. Both the medical-mediated and genetic depletion of p38MAPK in BeWo cells could suppress GLUT1 expression and OS-induced proapoptotic effects. Furthermore, blocking AMPK alpha with an inhibitor or siRNA strategy promoted p38MAPK, GLUT1, and proapoptotic molecules expression and vice versa. In general, a new GLUT1 regulation pathway was identified, which could exert effects on placental transport function through the AMPK alpha-p38MAPK pathway. AMPK alpha may be a therapeutic target in HIP for alleviating diabetes insults.