Conventional wisdom holds that, with the exception of skin and blood cells, most tissues in the body do not normally regenerate. But recent research has uncovered some surprising biological mechanisms that indicate that the body does in fact have the potential to repair some other vital tissues. Hoping to exploit this work, a Harvard University and University of Utah startup, Hydra BioSciences, is seeking to develop drugs that it says will repair damage from heart attacks.

Hydra's focus is on heart attack survivors-a group joined by hundreds of thousands of people in the United States every year-who are often left with damaged, scarred cardiac tissue that could lead to complete heart failure later in life. Current drugs don't repair the tissue, so Hydra is working on new treatments that will nudge mature heart-muscle cells to multiply again and ultimately form new, beating muscle. The three-year-old company's first project is to develop drugs that would be given to patients within a few weeks after a heart attack to trigger regrowth of the healthy cells near the injured area and prevent the heart from weakening and scarring. A similar therapeutic strategy could eventually work for a wide range of ailments and injuries, such as type I diabetes, retinal degeneration, spinal-cord injury, and Parkinson's disease, says Mark Keating, Hydra's cofounder and a researcher at Children's Hospital Boston.