Understanding heart metabolism

Researcher aims to jump-start energy-starved infant hearts

Gary LopaschukAt birth, the human heart—a high energy guzzler—undergoes a remarkable change. It switches from metabolizing mostly sugars, which powered it in the womb, to metabolizing mostly fatty acids.
“It’s one of the most dramatic physiological changes in your entire life, and it all happens within hours of birth,” marvels Dr. Gary Lopaschuk, distinguished professor and associate chair of research in the department of pediatrics at the University of Alberta.
With the help of a two-year Women and Children’s Health Research Institute innovation grant, Lopaschuk and his research team hope to better understand the molecular mechanisms underlying this switch in fuel consumption. The study builds on Lopaschuk’s earlier research and allows him to work with patients and families in the Stollery Children’s Hospital’s renowned pediatric heart surgical program.
The study may prove crucial for infants born with congenital heart defects, particularly when those defects cause the heart to become enlarged—a condition called cardiac hypertrophy. This condition also causes a delay in the metabolic shift from sugars to fats, making a bad situation worse. Not only are the hearts defective, but they can’t effectively process the energy they need to keep beating. Between two and three per cent of infants born in Alberta have some form of congenital heart defect and a significant number of these must undergo surgery. Hearts that have not matured metabolically tend to be starved of energy during and after surgery, notes Lopaschuk, who has received national and international achievement awards for his research.
If his study can reveal new information about what triggers the metabolic shift, researchers may then find a way to jump-start the process. “That’s our goal—not only to protect hearts during cardiac surgery, but to improve long-term heart function,” says Lopaschuk. “The children can have a more normal life because their hearts aren’t energetically starved.”
“We have some of the world’s best pediatric heart surgeons here. There’s great work being done, and we hope to make it that much better.”
Lopaschuk’s research has been funded by the generous support of the Stollery Children’s Hospital Foundation through WCHRI.