Nearly one out of every 100 babies in the U.S. is born with heart defects. But Michigan State University researchers are working to improve that outlook, leading to healthier children and happier families, with the help of a $2.2 million grant from the National Institutes of Health.
“Congenital heart defects are the most common birth defect in humans, affecting one out of 100 newborns. You might think that is not that many, relatively speaking,” said Aitor Aguirre, an assistant professor in the Department of Biomedical Engineering, who’s leading the project. “But think about Down syndrome, which is common. That affects one in 800.”
These heart defects, referred to collectively as congenital heart disease, are among the most common health conditions that patients face at birth. Treatments are challenging and usually aggressive, involving surgery and, in some cases, transplants.
Despite the prevalence of congenital heart disease and its profound impact, doctors and scientists don’t fully understand the cause in most cases.
“It can be genetic, but genetic causes are estimated to account for about 30% of cases,” said Aguirre, who is also a researcher in MSU’s interdisciplinary Institute for Quantitative Health Science & Engineering, or IQ. “What’s the other 50% to 70%? We don’t know.”
Still, knowing that the remainder isn’t genetics alone offers a clue. It means that environmental components, such as diet and nutrition, are important.
And Aguirre has recently discovered a new class of lipids, a type of molecule that includes fats, that provide important signals for the proper development of the heart during early pregnancy. Now, with the NIH grant, Aguirre and his colleagues will be able to more fully probe and characterize the connection between congenital heart disease and these lipids, which come from our diet.
“What this grant is going to enable us to do is dig into more details about how these lipids work and identify others,” Aguirre said. “If we can link congenital heart disease cases to dietary lipids, then, from a clinical standpoint, it could be very easy to prevent — maybe even treat — mothers at risk. It could be as easy as a supplement pill, similar to vitamins currently prescribed to pregnant women.”
To better understand that link between these lipids and heart health, the Spartan researchers will examine heart development and its biochemistry using conventional mouse models. But they’ll also take advantage of the first-of-its-kind miniature human heart model developed by Aguirre’s team, which models a human embryonic heart in the lab.
“It’s becoming more and more clear, as the years and decades pass, that mice are good models, but they are not perfect,” Aguirre said. “We’re bioengineering human mini-hearts that develop like they would inside the fetus’s body, but we’re doing it in a dish.”
Using these miniature heart models will help the team verify that its findings can translate to real patients, which is the ultimate goal of this work: to help newborns and their parents.
“Patients are our source of inspiration. When they come to us with problems, we start looking for answers,” said Joseph Vettukattil, who is a collaborator on the grant. Vettukattil is the division chief of congenital cardiology and co-director of the Congenital Heart Center at Spectrum Health Helen DeVos Children’s Hospital in Grand Rapids.
“When moms and parents ask me, ‘What can be done?’ or ‘What did I do wrong?’, it’s a hard question,” said Vettukattil, who is also a clinical professor in MSU’s Department of Pediatrics and Human Development. “The answer is congenital heart disease happens everywhere and we often don’t know the actual cause.”
By shining a light on the heart’s lipids, researchers could better understand how a mother’s diet affects a child’s heart development during pregnancy and provide parents with better answers.
“It’s a great driver and a great motivator to know that what we’re doing will have clinical value,” Aguirre said. “Even if this helps a small percentage of children at risk of congenital heart disease, that’s alleviating a lot of suffering.”