Research Notes – Study provides new look at folic acid and heart defects

In recent years, evidence has accumulated to show folic acid reduces congenital heart defects – the most common birth defect among newborns.

Research progress into this issue, however, has been limited, because few clues existed about the molecular or biological basis of folic acid’s effect on newborns.

Now a UNMC study led by Tom Rosenquist, Ph.D., vice chancellor for research, shows convincing evidence about the central role of a gene that regulates uptake of folic acid in cells that are the key to normal heart development.

Tom Rosenquist, Ph.D.

The research originally appeared in the June issue of the journal Developmental Dynamics and was included in the “Highlights” section of the journal’s August issue.

Gene blockers injected

The team injected customized gene blockers into selected cells of experimental chicken embryos to block a key gene used to make a receptor for folic acid.

At the same time, researchers injected a gene taken from a jellyfish that produces a protein that glows under special light. This let scientists follow the treated cells, which migrate into the developing heart and are required for formation of the separate ventricles, aorta and the pulmonary artery.

Other scientists Others from UNMC who worked on the study included: Gregory Bennett, Ph.D., associate professor, genetics, cell biology and anatomy; Richard Finnell, Ph.D., adjunct professor, pediatrics; and Tammy Chaudoin, research technician, genetics, cell biology and anatomy.

Slight disruption, major consequences

The surprising result was that a brief, 24-hour disruption of the flow of folic acid into these important cells had severe, permanent consequences, Dr. Rosenquist said.

This is significant, Dr. Rosenquist said, as it demonstrates the importance of genetic regulation of folate receptors, which grab passing folic acid and concentrate it into rapidly dividing heart-specific cells in early embryos.

More work remains

Since birth defects still occur in women who take folic acid, Dr. Rosenquist said more research is needed to determine the optimum dose or timing of folic acid or other vitamins and how they interact with the genetic make-up of the mother and/or the baby.