WEDNESDAY, April 18, 2012 (HealthDay News) -- Scientists report they were able to repair mouse hearts that were damaged by heart attacks.
Researchers from the Gladstone Institutes successfully converted scar tissue in the mice into beating heart muscle. Their findings, they said, might eventually lead to a similar treatment for people who've had heart attacks.
"The damage from a heart attack is typically permanent because heart-muscle cells -- deprived of oxygen during the attack -- die and scar tissue forms," Dr. Deepak Srivastava, who directs cardiovascular and stem cell research at Gladstone, a nonprofit biomedical research institution, said in a Gladstone news release. "But our experiments in mice are a proof of concept that we can reprogram non-beating cells directly into fully functional, beating heart cells -- offering an innovative and less invasive way to restore heart function after a heart attack."
In conducting the study, the researchers delivered three genes, known as GMT, involved in embryonic heart development directly into the damaged areas of the mouse hearts. They found the non-beating scar tissue was transformed into beating heart muscle within one month. The heart function of the mice improved even more after three months, the study added.
"These findings could have a significant impact on heart-failure patients -- whose damaged hearts make it difficult for them to engage in normal activities like walking up a flight of stairs," Li Qian, a postdoctoral scholar, who is also a California Institute for Regenerative Medicine postdoctoral scholar and a Roddenberry Fellow, said in the news release. "This research may result in a much-needed alternative to heart transplants -- for which donors are extremely limited. And because we are reprogramming cells directly in the heart, we eliminate the need to surgically implant cells that were created in a petri dish."
The next step, the study authors noted, is to duplicate their research and test its safety in larger mammals, such as pigs. This will bring the scientists one step closer to testing this type of treatment in people.
"We hope that our research will lay the foundation for initiating cardiac repair soon after a heart attack -- perhaps even when the patient arrives in the emergency room," said Srivastava, who is also a professor at the University of California, San Francisco, with which Gladstone is affiliated.
The findings were published online April 18 in the journal Nature.
In the future, the scientists say they hope this type of direct reprogramming will be used to also treat spinal cord injury and illnesses such as Alzheimer's and Parkinson's disease.
While the findings of the new study are promising, scientists note that research involving animals often fails to produce similar results in humans.
The U.S. National Heart, Lung, and Blood Institute provides more information on heart attacks.