Newborn Mice can Regenerate their Own Hearts

Newborn mice can regenerate their own hearts, found scientists from the University of Texas Southwestern Medical Center, quoted by the BBC. Working with newborn mice they found that a portion of the heart removed a day after birth could not only grow back, but was fully functioning within three weeks. Scientists in Texas are hoping their findings will provide a model for dealing with human heart problems.

They removed large chunks of heart out of mice that were only a day old, only to find that their hearts were restored within three weeks.

Previous research has demonstrated that some fish and amphibians can re-grow portions of their hearts after injury. However, this is the first time the process has been seen in mammals. Researchers at the University of Texas Southwestern Medical Center conducted the study and published their findings in the journal Science.

In the study, scientists at the University of Texas Southwestern Medical Center, showed that one-day-old mice could regenerate 15 percent of their heart tissue within three weeks, an ability that was lost if the procedure had been done when the mice were a week old. Also, heart scans showed that parts of the organ that had been surgically removed had not only grown back, but were functioning normally.

“Now that we know this process exists in mammals, which wasn’t recognized previously, we can try to find drugs, small molecules, or genes that can promote the process in humans. It’s been known for years that amphibians and fish have this regenerative ability, even in adulthood, but it was generally thought that this was lost in mammals. I was completely blown away by this result” said Eric Olson, a genetics and molecular biology professor at the University of Texas and an author of the study.

Olson thinks future research will show humans have a similar capacity, although no experiments involving human heart tissue are currently planned.

“There's no reason to believe that the same window would not exist in the human heart. Everything we know about development and early function of the mouse heart is comparable to the human heart so we're quite confident that this process does exist in humans, although that of course still has to be shown,” said Olson.

The team is now focusing on this brief window when the heart is still capable of regeneration, and to find out how, and why, the heart "turns off" this remarkable ability to regenerate as it grows older.

Newborn Mice can Regenerate their Own Hearts