Drug-coated blood stem cells have been used to repair heart damage in animal models by researchers at UT South-western Medical Centre.
It may open up the possibility for developing methods for healing injuries caused by heart attacks or disease.
For the study, researchers examined nearly 147,000 molecules to find one that could transform human blood stem cells into a form resembling immature heart cells.
When they implanted blood stem cells activated by this compound into injured rodent hearts, the human cells took root and improved the animals' heart function.
"The clinical potential is enormous," said Dr. Jay Schneider, assistant professor of internal medicine, senior author of the study and the cardiologist.
He also said that despite medical advances in treating and preventing heart attacks, once the heart is damaged it cannot repair itself.
In the first stage of the study involving mouse stem cells, the researchers examined some 147,000 compounds to identify which one would activate genes responsible for early stages of heart development.
They focused on a related group of molecules, called Shz for sulfonyl-hydrazone and later tested the effects of Shz-3, a molecular variant synthesized by chemists at UT Southwestern, on human blood stem cells.
These cells, called PBMCs for peripheral blood mononuclear cells, were cultured with Shz-3 for three days, then for seven days without the drug.
It showed that the Shz-treated cells began to create RNAs and proteins found only in heart cells. They were then implanted into the hearts of rats with heart damage.
The findings revealed that after a week, the function of the rats' hearts had significantly improved, and after three weeks, the organs contracted as strongly as they did before the damage, also human cells were alive and had incorporated themselves into the heart tissue.
"This functional test is a good first stepWhat this shows is that this drug can act on blood stem cells that are already being used in other clinical trials," said Dr. Schneider
"This may speed its movement into clinical trials for heart repair," he added.
The findings appear in Proceedings of the National Academy of Sciences.