Published on April 15, 2008 at 4:21 AM
Tests 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. 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. Tests showed that the human cells were alive and had incorporated themselves into the heart tissue, although the researchers could not tell whether the human cells had become fully functional, contracting heart cells.
“This functional test is a good first step,” Dr. Schneider said “What this shows is that this drug can act on blood stem cells that are already being used in other clinical trials. This may speed its movement into clinical trials for heart repair.”
Shz compounds do not appear to be toxic in mice, and because the human blood stem cells are washed for seven days after treatment, the compounds are likely not to be harmful to humans, although further tests are needed, Dr. Schneider said.
Further studies will examine precisely what the Shz drugs are doing to the cells, and to identify additional chemical signals that might drive the cells toward a more mature form of heart cell, the researchers said.