BOSTON - March 5, 2007 - Over the past several years, Joslin Investigator Mary R. Loeken, Ph.D., and her colleagues at Joslin Diabetes Center have unlocked several mysteries behind what puts women with diabetes more at risk of having a child with birth defects. Even though those risks have decreased significantly over the years, thanks in part to advancements at Joslin, women with diabetes still are two to five times more likely than the general population to have a baby with birth defects, especially of the heart and spinal cord, organs that form within the first few weeks of pregnancy.
In past work, Dr. Loeken and her research team were able to establish through their studies in mice that the mother's high blood glucose levels are the cause of these defects. This is one of the reasons why women with diabetes who are planning a pregnancy are encouraged to have their blood glucose levels under good control prior to conception. The Joslin researchers also have shown that the damage occurs because the extra glucose in the mother's blood inhibits the expression of embryonic genes that control essential developmental processes.
Now, in this latest study done in mice, Dr. Loeken and her colleagues have discovered that the protein called glucose transporter 2 (Glut2) makes it possible for the high concentrations of glucose to get into the embryonic cells efficiently when the mother's blood glucose concentrations are high. Also involved in the study was Rulin Li, Ph.D., a former postdoctoral fellow at Joslin. The study, supported by the National Institutes of Health, will appear in the March print edition of Diabetologia and was published online by the journal on Jan. 18.
"Glut2 is a gene that we wouldn't have expected to be switched on in early embryonic development," said Dr. Loeken, Investigator in the Section on Developmental and Stem Cell Biology and Associate Professor of Medicine at Harvard Medical School. "Yet our research in mic
Contact: Marjorie Dwyer
Joslin Diabetes Center