A team of researchers at Joslin Diabetes Center have identified an enzyme that may increase the likelihood of birth defects in children born to mothers with diabetes. The enzyme, known as AMPK, signals cells to stop producing a specific gene, PAX3. Without sufficient amounts of PAX3, the fetus is at increased risk of birth defects, including neural tube defects.

Studies have already revealed the connection between PAX3 and birth defects in children born to mothers with diabetes, but doctors did not understand how the PAX3 gene was suppressed. This study reveals that oxidative stress causes the body to produce the AMPK enzyme. This enzyme tells the nucleus of cells in the fetal body to stop producing PAX3. When PAX3 is inhibited, neural tube defects and other birth defects may occur. Neural tube defects are of particular concern because a healthy neural tube is the starting point for a healthy spine and brain.

Researchers specifically noted the effect of hyperglycemia on the fetus. Hyperglycemia, or high blood glucose, causes oxidative stress in the fetus. Oxidative stress occurs when more free radicals are produced than the body can control. The excessive amount of free radicals then leads to AMPK release and subsequent PAX3 inhibition.

While the research is noteworthy, it does not come with new treatment options. The only defense against AMPK is blood glucose control. Pregnant women with diabetes must maintain healthy blood glucose levels to prevent oxidative stress on the fetus. Currently, there is not enough information on AMPK to utilize medications that block the enzyme to reduce the risk of neural tube defects. AMPK could have positive and necessary effects on the fetus, so doctors have no clinical proof that blocking AMPK is safe.

Pregnant women with diabetes can help control blood glucose levels by eating a diet low in carbohydrates and taking all medications prescribed during pregnancy. Regular monitoring of blood glucose levels is important for fetal health. There are multiple treatment options available for pregnant women with diabetes, but doctors only know what patients report.

Source: Y. Wu, M. Viana, S. Thirumangalathu, M. R. Loeken. Diabetologia. 17 October 2011.