High concentration of glucose decreases glucose transporter-1 expression in mouse placenta in vitro and in vivo

Abstract

Facilitative glucose transporter-1 (GLUT1) is expressed abundantly and has an important role in glucose transfer in placentas. However, little is known about the regulation of GLUT1 expression in placental cells. We studied the changes in placental GLUT1 levels in relation to changes in glucose concentration in vitro and in vivo. In in vitro experiments, dispersed mouse placental cells were incubated under control (5·5 mM) and moderately high (22 mM) glucose concentrations, and 2-deoxyglucose uptake into cells was studied on days 1-5 of culture. After 4 days of incubation under both conditions, GLUT1 mRNA and proten levels were examined by Northern and immunoblot analyses. Treatment of cells with 22 mM glucose resulted in a significant decrease in 2-deoxyglucose uptake compared with control, from day 2 to day 5 of culture. Moreover, GLUT1 mRNA and protein levels on day 4 of culture were significantly reduced in cells incubated with 22 mM glucose compared with control. Next, we rendered mice diabetic by administering 200 µg/g body weight streptozotocin (STZ) on day 8 of pregnancy. Animals were killed on day 12 of pregnancy and placental tissues were obtained. [3 H]Cytochalasin B binding study was carried out to assess total GLUTs, and GLUT1 mRNA and protein were measured as above.[3 H]Cytochalasin B binding sites in placentas from STZ-treated mice were significantly less than those in control mice. Northern and immunoblot analyses revealed a significant decrease in GLUT1 mRNA and protein levels in diabetic mice compared with the controls. These findings suggest that the glucose concentration may regulate the expression of placental GLUT1.

Expression of glucocorticoid receptor and glucose transporter-1 during placental development in the diabetic rat

“…Ogura et al [29] demonstrated that GLUT 1 protein in placentas from diabetic mice was significantly decreased compared to controls. In spite of this, we determined that the expression level of GLUT 1 protein was not different in the developing normal rat placenta compared to diabetic placenta.…”

Id2 Mediates Differentiation of Labyrinthine Placental Progenitor Cell Line, SM10

“…Glucose uptake was assayed as previously described [15,53,69]. Briefly, the cells were plated at 2 · 10 4 cells/mL in 24-well plates.…”

AMPK Knockdown in Placental Trophoblast Cells Results in Altered Morphology and Function

“…Glucose and system L amino acid uptake were assayed as previously described [27,35]. Briefly, cells were plated at 1 · 10 4 cells in a 24-well plate for use the following day.…”