Implanting embryonic cardiac cells prevents arrhythmias

December 05, 2007

When researchers at Cornell, the University of Bonn and the University of Pittsburgh transplanted living embryonic heart cells into cardiac tissue of mice that had suffered heart attacks, the mice became resistant to cardiac arrhythmias, thereby avoiding one of the most dangerous and fatal consequences of heart attacks.

The discovery, reported in this week's issue of Nature, has profound implications for using cell-transplant therapies to restore damaged heart tissue.

The researchers, including Michael Kotlikoff, the Austin O. Hooey Dean of Cornell's College of Veterinary Medicine, one of the paper's senior authors, discovered that a protein called connexin43, expressed by the transplanted embryonic heart cells, improved electrical connections to other heart cells. The researchers showed that the improved connections helped activate the transplanted cells deep within the damaged section of the heart tissue. The technique reversed the risk of developing ventricular arrhythmias after a heart attack, the number one cause of sudden death in the Western world.

In the past, scientists have transplanted a variety of cell types into failing hearts with modest improvement of function, although transplanting skeletal muscle cells made things worse and led to more arrhythmias. Surprisingly, when co-author Bernd Fleischmann at the University of Bonn and colleagues transplanted embryonic cardiac cells, the hearts' electrical stability and function returned to normal.

Scientists recognize the untapped potential of using cell-based therapies to counter many debilitating diseases, but they have not had tools to assess the function of the cells once transferred. In Kotlikoff's laboratory, the researchers determined that the transplanted embryonic cells were making electrical connections with normal heart cells. Using genetically modified heart cells that express a fluorescent sensor, they established that transplanted heart cells were activated during normal heart contractions.

"For the first time we were able to see how cells used in therapy are working with other cells in a complex organ within a living animal, establishing the mechanism of the therapeutic effect," Kotlikoff said.

Professor Guy Salama at the University of Pittsburgh School of Medicine was also able to map voltage signals across the surface of the hearts, establishing that the implanted cells improve conduction of electrical signals within the damaged heart tissue.

While doctors could never use cells from a human embryonic heart for transplantation, researchers at the University of Bonn engineered skeletal muscle to express connexin43 and achieved the same restorative results as they did with the embryonic heart cells.

"These results have important implications for therapy, although they must be verified in the context of naturally occurring heart damage," Kotlikoff said. "One can envision using a patient's own cells by deriving heart cells from stem cells to improve heart function and decrease arrhythmia risk."
-end-
The study was supported by the National Institutes of Health, the Deutsche Forschungsgemeinschaft, the Federal Ministry of Education and Research, Germany, and the European Commission, Bonn Forschung.

Cornell University

Related Heart Attacks Articles from Brightsurf:

Additional heart imaging valuable for women with unexplained heart attacks
Combining diagnostic imaging methods can detect the underlying cause of heart attack in women who did not have blocked arteries.

How to treat the most common heart attacks
One in five patients die within a year after the most common type of heart attack.

Slow release of two chemicals protects the heart after experimental heart attacks
A novel treatment reduces heart damage after serious heart attacks in two animal models.

Heart attacks, heart failure, stroke: COVID-19's dangerous cardiovascular complications
A new guide from emergency medicine doctors details the potentially deadly cardiovascular complications COVID-19 can cause.

Declines in heart attacks greater among men than women
In a study published in the American Heart Association scientific journal Circulation, Kaiser Permanente research scientists report a steady decline in heart attacks for both men and women enrolled in the health system from 2000 to 2014, although that rate of decline slowed among women in the last 5 years of the study.

AI helps predict heart attacks and stroke
Artificial intelligence has been used for the first time to instantly and accurately measure blood flow, in a study led by UCL and Barts Health NHS Trust published in Circulation.

Nanoparticle chomps away plaques that cause heart attacks
Michigan State University and Stanford University scientists have invented a nanoparticle that eats away -- from the inside out -- portions of plaques that cause heart attacks.

Additional heart artery stenting reduces risk of future heart attacks
Research has shown that patients who have had emergency heart attack treatment with heart artery stenting -- and have significant narrowings in their other untreated arteries -- can benefit from additional stenting to help prevent future heart attacks.

How the enzyme lipoxygenase drives heart failure after heart attacks
Heart failure after a heart attack is a global epidemic leading to heart failure pathology.

Since 1990s, heart attacks have become less deadly, frequent for Americans
Heart attack prevention and outcomes have dramatically improved for American adults in the past two decades, according to a Yale study in JAMA Network Open.

Read More: Heart Attacks News and Heart Attacks Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.