Through a series of experiments, researchers showed that -- when given to mice that were induced to have heart attacks -- treatment with the protein, called thymosin beta-4, protected heart-muscle cells from dying and was associated with improved heart function.
"If it works in humans, it will be very useful for protecting the heart after a heart attack," said Deepak Srivastava, professor of molecular biology and pediatrics at University of Texas Southwestern Medical Center Dallas. He is senior author of a paper on the experiments, which appears in the current issue of the journal Nature.
Translating results of experiments with mice to people is a daunting challenge and few new treatments clear the hurdle. Thymosin beta-4 already is being studied in people as a possible wound-healing treatment, and Dr. Srivastava said plans for human studies of its use in heart attack are on the drawing board. The protein is being developed by RegeneRx Biopharmaceuticals Inc., a small Bethesda, Md., company.
During a heart attack, blockages in the coronary arteries cut off oxygen to the heart muscle, resulting in the death of tissue that can permanently weaken the heart. Because the heart lacks sufficient capacity to heal the damage, survivors of heart attacks typically develop congestive heart failure, a progressive and debilitating condition that kills 20% of patients within a year of diagnosis.
The treated mice ended up with less muscle damage and stronger hearts several weeks after the heart attack than those given saline.