For a long time, the heart was considered a postmitotic organ with a lack of regenerative capacity, i.e., dead myocardium cannot be replaced with functional myocardial tissue. At first clinical glance, this fact has not changed. For some years now, there has been increasing scientific evidence that the heart does have a regenerative capacity. However, this is far from sufficient to compensate for clinically significant cardiac disease.
Together with other research groups, we succeeded in demonstrating an excellent regenerative capacity of newborn mouse hearts and demonstrated complete regenerative capacity after clinically relevant myocardial infarction. Additional evidence from other mammalian experimental models and even case reports of human babies confirm the great plasticity of neonatal mammalian hearts.
In our lab we address the questions of what are the molecular mechanisms of neonatal cardiac regeneration, and can we translate the answers to heal adult human hearts?
Figure. Serial sections cut longitudinally from the back- to the front wall of the hearts harvested 30 days post injury or sham surgery. Tissue sections were stained with trichrome and aniline blue; blue demarks fibrosis, whereas viable cardiomyocytes are brick red. Arrowheads point at the site of myocardial infarction in hearts ligated at postnatal day 7. Asterisks indicate the locations of the ligatures. LAD left anterior descending artery, P0.5 postnatal day 1, P7.5 postnatal day 7. Haubner BJ, Schuetz T, Penninger JM. Basic Res Cardiol. 2016.