Mammalian Hearts Capable of Regrowing February 26, 2011Posted by Metabiological in Longevity, Transhumanism.
Tags: heart disease, regenerative medicine, science, transhumanism
One of the primary reasons that heart disease is the number one killer in the developed world is the fact that once heart muscle is damaged it is incapable of regrowing. Or so we thought.
The researchers found that within three weeks of removing 15 percent of the newborn mouse heart, the heart was able to completely grow back the lost tissue, and as a result looked and functioned just like a normal heart. The researchers believe that uninjured beating heart cells, called cardiomyocytes, are a major source of the new cells. They stop beating long enough to divide and provide the heart with fresh cardiomyocytes.
I’m somewhat surprised that rather than cardiac stem cells playing a role in the process the new cells seem to grow from existing mature heart tissue. Considering the researchers mentioned the heart cells needing to stop beating in order for the division to take place it makes me wonder if that may have something to do with this feature being lost as we grow older. For an adult individual needing to largely fend for itself the loss of some cardiac output could represent a severe loss in fitness, a difference that may not be overcome by the benefit of being able to regenerate damaged heart cells.
Now of course all the usual caveats apply. This was in mice not humans. Its only one study. It only works in juvenile hearts. But as a proof on concept it is very exciting especially given the aforementioned seriousness of heart disease as both an individual and societal problem for much of the west.