Free radicals are the language of the heart

Free radicals are usually associated with aging, heart disease and neurodegenerative conditions. But researchers at OMRF have found that free radicals are also vital to normal heart function.

When cells use oxygen to create energy, they create free radicals as a byproduct, said OMRF researcher Hui-Ying Lim, Ph.D.

“Most people talk about free radicals as if they’re only harmful, and there’s plenty of evidence linking them to many different diseases,” she said. “That’s the rationale behind the surge in antioxidants, which are supposed to trap free radicals. But increasingly, we’re seeing that free radicals are also necessary for human health.”

In a paper published in the journal Cell Reports, Lim and fellow OMRF researcher Weidong Wang, Ph.D., describe how the presence of free radicals in pericardial cells—cells which surround the heart—are used to communicate with heart cells called cardiomyocytes.

“The first heart transplant took place almost 50 years ago, but while surgeons have become skilled at replacing damaged hearts, we’re still not sure what makes hearts beat properly,” she said. “The molecular mechanisms that drive our hearts are still a big mystery.”

OMRF scientists, working with Rolf Bodmer, Ph.D., of the Sanford Burnham Medical Research Institute in La Jolla, Calif., used fruit flies, which have a simple tube as a heart, to make their discovery.

“We’ve found that moderate amounts of free radicals are essential for heart function,” she said. “They may still cause problems in overt amounts, but they serve an important role in the heart at optimal levels.”

The next step in the research will be to further investigate the role of free radicals in the hearts of fruit flies and to explore the potential relevance of their findings in mice, she said.

“The molecular workings of heart cells are still a puzzle, but we think this is an important finding in expanding our understanding in this area,” Lim said. “The more we know, the better future treatments we can develop for heart diseases.”

The research was funded by grant No. 5P20GM103636-02, from the National Institute of General Medical Sciences, a part of the National Institutes of Health, and grants No. 13SDG14680005, 10POST4140064 and 0825276F from the American Heart Association.