Their Hearts Will Go On

Mammalian newborn hearts can heal themselves completely, according to new research from the University of Texas Southwestern Medical Center.

A portion of the heart removed during the first week after birth in mice grew back completely without incident.

Dr. Hesham Sadek, assistant professor of internal medicine and senior author of the study, said this finding represents an important step in finding a cure for heart disease.

However, adult mammals lack the capacity to regrow lost or damaged tissue. As a result, when the heart of an adult is injured by a heart attack, it grows weaker and eventually can lead to heart failure.

A newborn mouse heart was able to completely grow back within three weeks after removing 15 percent of the organ. Researchers believe uninjured cardiomyocytes (beating heart cells) provided the new cells by stopping beating long enough to divide and provide fresh cardiomyocytes.

Co-senior author of the study, Dr. Eric Olson, who directs the Nancy B. and Jake L. Hamon Center for Basic Research in Cancer and the Nearburg Family Center for Basic and Clinical Research in Pediatric Oncology, said this information will allow researchers to discover methods to reawaken cardiac regeneration in adulthood.

Heart disease is the No. 1 killer of men and women in the developed world.