Problems associated with the aging heart could be reversed by infusing the organ with a type of cell taken from a young heart. According to a study published last week in the European Heart Journal, elderly rats injected with a specific type of stem cell showed a significant improvement in their health and vitality. The cardiosphere-derived cells helped reverse signs of aging in animals with an average age of 22 months, which is considered old for a rat. They were more agile and even showed better hair growth than animals in a control group. In this in-depth interview, Dr. Lilian Grigorian, the study’s co-primary investigator at the Cedars-Sinai Medical Center Heart Institute in Los Angeles, explains how the research was carried out, and why some of the results came as a surprise. She says the “incredibly motivating” findings could have “exciting” implications for human heart health and longevity within the next ten years.