Stem Cell Therapy Restores Youthful Heart Performance

Cardiac disease researchers have demonstrated in a rat model that injections of cardiosphere-derived cells from young rats could rejuvenate the hearts of aged animals.

Investigators at Cedars-Sinai Heart Institute (Los Angeles, CA, USA) worked with cardiosphere-derived cells (CDCs) provided by the biotechnology company Capricor Inc. (Beverly Hills, CA, USA).

Cardiospheres (CSps) are clusters of stem cells obtained from heart muscle, while cardiosphere-derived cells (CDCs) are CSp cells that have been formatted into a single layer. CDCs possess regenerative properties, which are expressed not by becoming part of the recipient’s heart, but by acting at a distance to cause cells in the recipient heart to divide and/or differentiate. CDCs in doses sufficient for activity can be injected into the coronary arteries without damaging the heart muscle. Since CDCs originate in the myocardial cell lineage, they are particularly well-suited to stimulate the heart’s innate restorative capabilities.

While the heart muscle appears capable of healing from daily “wear and tear,” its repair systems are insufficient to address extensive damage such as that which results either from an acute event, such as a heart attack, or from chronic injury, which may be associated with a variety of conditions. Following their infusion, CDCs track to the area of injury and release growth factors and cytokines that signal the heart to repair itself. Although the infused CDCs are eventually cleared from the body, their beneficial effects are believed to be long-lasting.

In the current study, the investigators injected CDCs from newborn rats into the hearts of rats with an average age of 22 months, which is considered aged. A control group of aged animals received a placebo treatment, saline injections instead of stem cells. Heart responses of both groups of aged rats were compared to a group of young rats with an average age of four months. Baseline heart function was measured in all rats, using echocardiograms, treadmill stress tests, and blood analysis.

Results published in the August 14, 2017, online edition of the European Heart Journal revealed that CDCs, but not PBS, restored a youthful pattern of gene expression in the hearts of old animals, and telomeres in heart cells were longer in CDC-transplanted animals. In addition, the animals receiving CDCs experienced improved heart function, enhanced their exercise capacity by an average of approximately 20%, regrew hair faster, and showed reduced levels of serum biomarkers of inflammation (IL-10, IL-1b, and IL-6).

"Our previous lab studies and human clinical trials have shown promise in treating heart failure using cardiac stem cell infusions," said senior author Dr. Eduardo Marbán, director of the Cedars-Sinai Heart Institute. "Now we find that these specialized stem cells could turn out to reverse problems associated with aging of the heart. The way the cells work to reverse aging is fascinating. They secrete tiny vesicles that are chock-full of signaling molecules such as RNA and proteins. The vesicles from young cells appear to contain all the needed instructions to turn back the clock."

Related Links:
Cedars-Sinai Heart Institute
Capricor