The Future of Cardiovascular Regenerative Medicine

For centuries, biologists have studied salamanders that can regrow entire new limbs after amputation. Flatworms, when beheaded, grow a new head from the beheaded corpse (and the severed head grows a new body).1 All species, from bacteria to plants to animals, can regenerate to some degree, and it has been said that without regeneration, there could be no life.2 In fact, humans regenerate many of their tissues, including skin, blood, liver, and intestinal mucosa, routinely, efficiently, and often perfectly. Skeletal muscle regenerates remarkably well; every time we strain a muscle, muscle stem cells repair the injury, and this is a key component of the conditioning associated with exercise training. But the adult human heart appears to have little of the regenerative ability of our skeletal muscles. The challenge of this limitation has triggered considerable enthusiasm in using different types of stem cells to repair failing human hearts. We will not review this substantial effort in human cardiac cell therapy, because expert reviews have been published recently.3–5 Here, we attempt to predict where regenerative biology and its translational discipline, regenerative medicine, will take us in the future, with a focus on cardiovascular medicine.Regenerative biology has many definitions, but a simple one is the study of how organisms replace lost or damaged tissue with new tissue. We are now entering an era where regenerative biology is turning from science fiction into science, with realistic regenerative medical applications beginning to emerge. This change is based on a broader and more fundamental understanding of cell biology, and this new view has laid a foundation for the potential repair of organs that were previously viewed as being incapable of regeneration or even modest repair. The explosion of interest in regenerating diseased hearts and other organs is being fueled by …