Boston, MA – Recent research has shown that there are new cells that develop in the heart, but how these cardiac cells are born and how frequently they are generated remains unclear. In new research from Brigham and Women's Hospital (BWH), researchers use a novel method to identify these new heart cells and describe their origins.
This research is published in Nature on December 5, 2012.
A sophisticated imaging system (MIMS) demonstrates cell division in the adult mammalian heart.
"The question about how often cardiac cells are born has been extremely difficult to answer because there was a need for new techniques to help us understand this process. We are especially excited about our findings because of the novel way in which were able to show new heart cells, using Multi-isotope Imaging Mass Spectrometry (MIMS). Our collaborator, Claude Lechene, MD, had developed this technology, and as a team we harnessed this for the cardiac regeneration question." said Richard T. Lee, MD, a physician and researcher in the Cardiovascular Division at BWH and senior author of the paper. "These data present one piece of the puzzle when it comes to the discussion around the generation of new cardiac cells."
The team of BWH researchers marked existing cardiac cells genetically to cause them to express a green fluorescent protein. Then they used Multi-isotope Imaging Mass Spectrometry (MIMS) to examine the development of new heart muscle cells, called cardiomyocytes, in a pre clinical model over a period of months. Researchers were surprised to find that new heart muscle cells primarily arose from existing heart muscle cells, rather than stem cells. Even in the setting of a heart attack, when stem cells are thought to be activated, most new heart cells were born from pre-existing heart cells.
"Our data show that adult cardiomyocytes are primarily responsible for the generation of new cardiomyocytes and that as we age, we lose some capacity to form new heart cells," said Dr. Lee. "This means that we are losing our potential to rebuild the heart in the latter half of life, just when most heart disease hits us. If we can unravel why this occurs, we may be able to unleash some heart regeneration potential."
This research was funded through grants from the National Institutes of Health (F32 HL108570, K08 DK090147, EB001974, AG034641, AG032977, AG040019), The American Heart Association (AHA FTF), Future Leaders in Cardiovascular Medicine, Watkins Cardiovascular Leadership Award and the Ellison Medical Foundation (AG-SS-2215-08).
Brigham and Women's Hospital (BWH) is a 793-bed nonprofit teaching affiliate of Harvard Medical School and a founding member of Partners HealthCare. BWH has more than 3.5 million annual patient visits, is the largest birthing center in New England and employs more than 15,000 people. The Brigham's medical preeminence dates back to 1832, and today that rich history in clinical care is coupled with its national leadership in patient care, quality improvement and patient safety initiatives, and its dedication to research, innovation, community engagement and educating and training the next generation of health care professionals. Through investigation and discovery conducted at its Biomedical Research Institute (BRI), BWH is an international leader in basic, clinical and translational research on human diseases, involving nearly 1,000 physician-investigators and renowned biomedical scientists and faculty supported by $640 million in funding. BWH continually pushes the boundaries of medicine, including building on its legacy in organ transplantation by performing the first face transplants in the U.S. in 2011. BWH is also home to major landmark epidemiologic population studies, including the Nurses' and Physicians' Health Studies, OurGenes and the Women's Health Initiative. For more information and resources, please visit BWH's online newsroom.
Journal
Nature