Galectin-3 expression among women with gestational diabetes type 2

Gestational diabetes mellitus (GDM) is defined as glucose intolerance that was diagnosed during pregnancy. It is one of the most common complications of pregnancy, and has short-and long-term effects on both the mother and child, specifically, an increased risk of diabetes mellitus and cardiovascular diseases. It is categorized as diet-controlled gestational diabetes (GDMA1) or gestational diabetes that requires medication (GDMA2). Galectin-3 (Gal-3) is a galactoside-binding lectin that mediates interactions with numerous ligands of significance in the process of cell growth, differentiation, inflammation, and fibrosis. We evaluated Gal-3 mRNA and protein expression in maternal serum, placenta, and umbilical blood cord of women with GDMA2 and normal pregnancies (NP). Sixty pregnant women (30 with GDMA2 and 30 NP) were recruited during admission for delivery. Blood samples were obtained from the parturients and umbilical cords, as well as placental tissue for mRNA, protein extraction and immunohistochemistry. Gal-3 mRNA expression was significantly increased in maternal serum and placentas of women with GDMA2 compared to NP (fold expression ratio 3.18±1.22; P=0.03 and 13.78±2.70, P=0.008, respectively). Gal-3 mRNA was decreased in GDMA2 cord blood (fold expression ratio 0.37±0.08, P<0.01) compared to NP, as well as to GDMA2 maternal serum mRNA and GDMA2 placental mRNA. Gal-3 GDMA2 placental protein expression was increased compared to NP (fold expression ratio 2.41±0.26, P=0.03). Immunostaining revealed that Gal-3 is significantly upregulated in GDMA2 placental villous trophoblast. Our findings suggest that although Gal-3 is strongly expressed in GDMA2 maternal serum and placental tissue, it is decreased in cord blood. It implies that the placenta protects the fetus from the damages of inflammatory responses, which are common in a diabetic environment.View Large Image Figure ViewerDownload Hi-res image Download (PPT)