AHA: Modification of Stem Cells Promising for Heart Failure
Overexpression of Pim-1 increases cell cycling time, telomere length in aged heart stem cells
TUESDAY, July 24 (HealthDay News) -- Modification of aged human cardiac progenitor cells (hCPCs) from elderly patients with Pim-1, a protein that promotes cell survival and growth, improves their ability to regenerate damaged myocardium, according to a study published in the Journal of the American College of Cardiology to coincide with presentation at the American Heart Association's Basic Cardiovascular Sciences 2012 Scientific Sessions, held from July 23 to 26 in New Orleans.
Sadia Mohsin, Ph.D., from the San Diego State University, and colleagues isolated hCPCs from three patients aged 75 to 85 years with heart failure undergoing left ventricular assist device implantation. The hCPCs were engineered ex vivo to express Pim-1.
The researchers found that hCPCs from 75- to 85-year-old patients demonstrated reduced population doubling time, decreased telomere lengths as measured by in situ hybridization, and decreased telomerase activity assessed by Telomere Repeat Amplification Protocol assay, relative to three patients aged 60 to 73 years. Following overexpression of Pim-1 in hCPCs isolated from old patients, there was an increase in cell cycling time measured by population doubling. There was a significant increase in telomere length and telomerase activity indicative of reverse of senescent characteristics of aged hCPCs seen with Pim-1 modification.
"Modifying aged human cardiac cells from elderly patients adds to the cell's ability to regenerate damaged heart muscle, making stem cell engineering a viable option," Mohsin said in a statement. "This is an especially exciting finding for heart failure patients. Right now we can only offer medication, heart transplantation, or stem cell therapies with modest regenerative potential, but Pim-1 modification offers a significant advance for clinical treatment."