Researchers at Boston Children's Hospital have found, for the first time that young humans (infants, children and adolescents) are capable of generating new heart muscle cells. These findings refute the long-held belief that the human heart grows after birth exclusively by enlargement of existing cells, and raise the possibility that scientists could stimulate production of new cells to repair injured hearts.
Findings of the study, "Cardiomyocyte proliferation contributes to post-natal heart growth in young humans," were published in Proceedings of the National Academy of Sciences, Online Early Edition, the week of Jan 7-Jan 11, 2013. The study was led by Bernhard Kühn, MD, of the Department of Cardiology at Boston Children's.
Beginning in 2009, Dr. Kühn and his team looked at specimens from healthy human hearts, ranging in age from 0 to 59 years. Using several laboratory assays, they documented that cells in these hearts were still dividing after birth, significantly expanding the heart cell population. The cells regenerated at their highest rates during infancy. Regeneration declined after infancy, rose during the adolescent growth spurt, and continued up until around age 20.
The findings offer the strongest evidence to date that proliferation of cardiomyocytes (the cells making up heart muscle) contributes to growth in healthy young human hearts.
"For more than 100 years," Kühn says, "people have been debating whether human heart muscle cells are generated after birth or whether they simply grow larger." Kühn points out that research in the 1930s and 1940s suggested that cardiomyocyte division may continue after birth, and recent reports about myocardial regeneration in zebrafish and neonatal mice suggest that some young animals regenerate heart muscle by using mechanisms of muscle cell division. Still, for many years, the accepted belief in the scientific community was that human hearts grow after birth only because cells grow larger.
Kühn's work challenges the accepted wisdom and offers hope for new treatments for heart failure. Babies and children may be able to increase heart muscle cell proliferation and regenerate damaged parts of their heart muscle. In addition, the study points to new research directions by suggesting that abnormal cardiomyocyte proliferation may be involved in diseases of the heart muscle (cardiomyopathy) that affect young humans, and that cardiomyocyte proliferation could be stimulated in young humans for the treatment of heart failure.
The findings, according to Kühn, help to create a "cellular blueprint for how the human heart grows after birth." Using this blueprint, treatment strategies could be developed to treat heart failure in children
Boston Children's Hospital: http://www.childrenshospital.org/newsroom
This press release was posted to serve as a topic for discussion. Please comment below. We try our best to only post press releases that are associated with peer reviewed scientific literature. Critical discussions of the research are appreciated. If you need help finding a link to the original article, please contact us on twitter or via e-mail.
The largest specimen among Earth's first flying vertebrates boasted a 10-metre wingspan, dwarfing modern-day giants Continue reading...
How can creatures as different in body and mind as present-day humans and their extinct Neanderthal cousins be 99.84 percent identical genetically?
A mile deep expedition using robots has discovered three ships that sank off the coast of Galveston centuries ago. Archeologists are still unsure of why the vessels sunk.
Scientists based their technique on the one used to create the sheep Dolly years ago. These cells might one day be useful in treating all sorts of diseases.
It turns out the first chili peppers were grown by humans in eastern Mexico. And it's not the same region where beans and corn were first grown, according to new ways of evaluating evidence.
A team of international scientists have found four species of insects with reversed sex organs. The females' anatomy may have to do with their need for nutrients that only males produce.
For all but the shyest of wallflowers, moving to music is a natural human response. But what is it about a catchy tune that makes us groove? Scientists think they've figured out at least part of the recipe: just the right mix of regular rhythms and unexpected beats.
Artists' brains are structurally different to non-artists in areas relating to fine motor movements and visual imagery, a study finds.
Information about who suspects call and when is helping police work out who is linked to which crimes and even their place in the criminal hierarchy
The lead scientist behind a revolutionary method to turn adult cells into stem cells has been found guilty of misconduct, but insists the mistakes were unintentional