The results of the study reveal the reason why babies born to women with diabetes have a higher chance of developing congenital heart disease.
Atsushi "Austin" Nakano, a UCLA associate professor of molecular, cell, and developmental biology and member of the Broad Stem Cell Research Center, led the study.
Per the team of researchers, "when developing heart cells are exposed to high levels of glucose," cells generate more building blocks of DNA than usual. This causes the cells to keep reproducing instead of maturing.
Nakano said, "High blood sugar levels are not only unhealthy for adults; they're unhealthy for developing fetuses... Understanding the mechanism by which high blood sugar levels cause disease in the fetus may eventually lead to new therapies."
While genetics is a significant factor in the development of congenital heart disease, one leading non-genetic risk factor for the disease is a pregnant woman diagnosed with diabetes during pregnancy. Babies born to women with high levels of glucose in their blood during pregnancy are twice or even five times more likely be diagnosed with diabetes than other infants. The problem is, scientists are unable to isolate the specific effect of glucose on the developing fetus. (Related: Nutritional supplement helps prevent gestational diabetes.)
Nakano et al. worked with human embryonic stem cells to grow cardiomyocyte (heart muscle cells) in the lab which was then exposed to different glucose levels. Cells exposed to small amounts of glucose matured normally, but cardiomyocytes combined with high levels of glucose matured late or failed to mature altogether. The second batch of cardiomyocyte even "generated more immature cells."
Because of the extra glucose, "the cardiomyocytes over-activated the pentose phosphate pathway," which is a cellular process that generates nucleotides, or the building blocks of DNA. In cells with high glucose levels, the pentose phosphate pathway made more nucleotides than usual. The scientists showed that the excess of building blocks kept the cells from maturing.
Nakano shares that when it comes to these cells, more nutrition can actually be bad for them. Depleting glucose at a specific development point can help the cells mature and strengthen the heart muscle.
Nakano adds that the results of their study can pave the way for improved methods of forming cardiomyocytes from stem cells. Though most protocols for generating cardiomyocytes in the lab lead to immature cells, focusing on the pentose phosphate pathway "could help generate more mature cells for regenerating heart cells or for research purposes."
If you're with child and are diagnosed with diabetes, try to eat more of the foods below to lower your blood sugar:
Sources include: