Searching for a Heart Defect Treatment for Preemies

Searching for a Heart Defect Treatment for Preemies

UNT Diving Eagle
April 8, 2021

Ed Dzialowski, a developmental comparative physiologist who studies the similarities and differences of anatomy and physiology between species, is conducting cardiopulmonary research that could assist the treatment or prevention of a common birth defect in premature infants.

Funded by a grant from the National Institutes of Health, he and his research team are studying the ductus arteriosus -- the fetal artery connecting the aorta and pulmonary artery. The ductus arteriosus allows blood to detour away from the lungs before birth. In healthy, full-term newborns, it closes shortly after birth. In infants born prematurely, it often does not close, causing a condition known as patent ductus arteriosus, or PDA, which requires medical intervention that may require surgery to close the blood vessel.

“I’m interested in how the cardiovascular and respiratory systems develop and function,” Dzialowski, professor of biological sciences and associate dean for research and graduate studies, says adding his research is focused on the cellular pathways that are involved in the constriction of the ductus arteriosus and how those pathways develop.

He’s hoping to find an alternative treatment to surgery by using drugs to stimulate the contractile pathway. His team is examining at what stage in fetal development the blood vessel is triggered to close after birth and what makes that happen.

“We are looking at a pathway that works in other smooth muscles, but it hasn’t yet been explored in this blood vessel,” Dzialowski says that they’re asking “What is the timing of the development of those pathways and what pathways are important or have to be in place in order for the blood vessel to respond properly for it to close at birth?” 

The main goal of the NIH study is to look at a specific pathway, actin polymerization, and its role as a potential pathway involved in ductus arteriosus closure. Dzialowksi’s team is looking across species to compare and understand when during development the pathway first appears as a mechanism for closure. 

“An interesting thing about this blood vessel is that it’s found in the embryonic or fetal stage of all land vertebrates – amphibians, reptiles, birds and mammals,” Dzialowski says adding he uses birds, chickens in this case, as models in his research because the pathways he is studying are very similar in birds and in mammals. 

Birds develop in an egg, and researchers can easily control and monitor the environment of the fetus as it develops. The same is true for reptiles, and Dzialowski has looked at the ductus arteriosus in alligators during previous studies. Once they find the answers in birds, the research will need to be confirmed in mammals. The results from this study will provide new targets to explore for successful intervention of a PDA in humans. 

“In gaining a better understanding of the pathways and how they work, we hope to learn how to better treat PDA,” he says.