Researching Stem Cells For Cardiac Treatment
As the debate over using stem cells for medical research continues at the national level, researchers and clinicians at The Ohio State University Medical Center are studying the effectiveness of using non-embryonic stem cells to regenerate heart muscle to improve outcomes for patients.
Earlier this year, Ohio State researchers found that “pretreating” adult stem cells with an anti-angina drug allows them to better adapt to the harsh environment of their transplantation site. Scientists are studying whether transplanted cells eliminate or slow the tissue deterioration that would lead to heart failure.
In research published in the Journal of Pharmacology and Experimental Therapeutics, adult stem cells from the bone marrow of rats were pretreated with the drug trimetazidine, or TMZ. The stem cells were then grown under low oxygen conditions to mimic their native and destination environments, and then exposed to stressful conditions that exist in the damaged heart tissue. The pretreated stem cells provided a substantially better therapeutic effect in restoring heart function.
“Transplanted stem cells can repair many types of damaged tissue, including heart tissue,” says Dr. Periannan Kuppusamy, associate director of the Ohio State Medical Center’s Dorothy M. Davis Heart and Lung Research Institute. “However, most of the stem cells transplanted in the heart die within a few days due to lack of oxygen and nutrients.”
Stem cell-based cardiac therapy is an experimental procedure in which stem cells are transplanted to the damaged region of the heart in patients who have suffered a heart attack. Funding from the National Institutes of Health supported Kuppusamy’s research.
In early 2008, OSU Medical Center’s Richard M. Ross Heart Hospital began collaborating with Arteriocyte, a biotechnology company created at Case Western Reserve University, to develop stem-cell therapies for human use.
“The biggest challenge is that heart muscle doesn’t typically regenerate,” says Dr. Vincent Pompili, Ohio State’s director of cardiovascular cell-based therapies, who previously served at University Hospitals Case Medical Center. “These studies are allowing us to study individual disease processes and identify ways to accelerate the body’s healing mechanisms.”
Two recent Phase I trials offer a glimpse into the potential of stem-cell therapy. The first infused a very low dose of umbilical cord blood stem cells into patients with chronic ischemia, a condition characterized by a constant lack of blood and oxygen supply to the heart. After receiving the stem cells, a significant number of trial participants saw improved blood flow to the heart. According to Pompili, this resulted from the stem cells’ ability to help the body repair itself.
The second study examined the effect of human umbilical cord blood stem cells in genetically-engineered mice experiencing a chronic lack of blood flow to one of their limbs. One month after stem cell infusion, researchers noted nearly normal blood flow in the mice limbs.
“Although this research is still in its early stages, it holds great promise as a potential therapy for patients suffering from a chronic lack of blood flow to and from the heart,” adds Pompili, who also serves as Ohio State’s section director of interventional cardiology. “Ohio State’s partnership with biotechnology companies illustrates our commitment to offering stem cell therapies in cardiovascular medicine.”