Study Backs Idea that Heart can Repair Itself
Challenging generations of medical lore, researchers have found striking new evidence that the human heart can repair itself Doctors have long assumed that damage from a heart attack or other ailment is irreversible and that the heart cannot regenerate tissue the way other organs can. But last year a team of American and Italian researchers demonstrated that heart muscle cells multiplied after a heart attack.
And now they have shown that in heart transplant patients, primitive cells from the patient travel to the new heart and grow new muscle and blood vessels. Studying men who received transplanted hearts from women, the researchers discovered male cells in the donated female hearts cells that could only have come from their own bodies.
“There have been hints from animal studies that the cells could migrate before, but this is the first demonstration in a human that it is actually possible.” said John Fakunding of the National Heart, Lung and Mood Institute. The Institute helped pay for the study, which appears in The New England Journal of Medicine.
The researchers found that heart muscle and blood vessels grew rapidly in the new hearts after transplant. They calculated that as much as one fifth of the donor heart had been rebuilt by the recipient’s own cells.
“Clearly this shows that the heart has the ability to regenerate,” said Dr. Roberto Bolli of the University of Louisville, who wrote an accompanying editorial. “It could be a milestone discovery if we learn how to exploit this phenomenon for therapeutic purposes to regenerate heart muscle in patients with heart failure.”
After the heart recipients died, tissue samples were taken from each donor heart and from remnants of the old heart not removed during transplant surgery.
The researchers found evidence of the primitive cells with stem cell characteristics in the remnants of the old hearts, as well as in the donor hearts.
“We have the first strong suggestions that the heart has primitive cells meaning cardiac stem cells which could be used in the future to repair the heart,” said Dr. Piero Anversa, who led the researchers at New York Medical College in Valhalla, N. Y., and the University of Udine and the University of Parma in Italy.
Dr. Anversa said he and his colleagues were working to identify whether a cardiac stem cell existed and whether it could be manipulated to promote heart repair.
Reprinted from the New York Times, January 2, 2002
Severed Spinal Cords Coaxed to Regenerate
ST LOUIS – A transected spinal cord can be induced to regenerate if the gap is filled at the right time with a bridge of peripheral-nerve tissue through which axons can grow, reports a Washington, D.C., neurosurgeon. Dr. Carl C. Kao offers as proof five dogs that regained the ability to walk three months after their cords were irreversibly crushed. Operating a week or two after the injury, the Georgetown University associate professor of surgery and anatomy removed the dead cord tissue, filled the gap with pieces of limb nerve, and coated the cut cord ends with cultured peripheral-nerve cells. The operation could not help long-paralyzed patients, he told the Society of Neuroscience meeting here. But clinical trials on patients with fresh cord injuries may start within a year, if new studies on cats give good results.
Medical World News 1979
Manhattan – Scientists may have found a way to generate unlimited supplies of brain cells for transplanting into Parkinson’s disease patients, but the source of those cells fetuses and animals that could introduce new diseases into humans is problematic.
New work is focusing on growing brain cells, called neural stem cells, in the lab. Scientists have done it with mice and now are studying how to reproduce the results with human cells to get the cells they need.
In a new study, researchers reported producing brain cells that pump out the chemical dopamine-the kind of cell that is transplanted in Parkinson’s disease.
Daily News, June 29, 1999 ll.