Molecular basis of functional myogenic specification of Bona Fide multipotent adult cardiac stem cells

Ischemic Heart Disease (IHD) remains the developed world’s number one killer. The improved survival from Acute Myocardial Infarction (AMI) and the progressive aging of western population brought to an increased incidence of chronic Heart Failure (HF), which assumed epidemic proportions nowadays. Except for heart transplantation, all treatments for HF should be considered palliative because none of the current therapies can reverse myocardial degeneration responsible for HF syndrome. To stop the HF epidemic will ultimately require protocols to reduce the progressive cardiomyocyte (CM) loss and to foster their regeneration. It is now generally accepted that mammalian CMs renew throughout life. However, this endogenous regenerative reservoir is insufficient to repair the extensive damage produced by AMI/IHD while the source and degree of CM turnover remains strongly disputed. Independent groups have convincingly shown that the adult myocardium harbors bona-fide tissue specific cardiac stem cells (CSCs). Unfortunately, recent reports have challenged the identity and the endogenous myogenic capacity of the c-kit expressing CSCs. This has hampered progress and unless this conflict is settled, clinical tests of repair/regenerative protocols are unlikely to provide convincing answers about their clinical potential. Here we review recent data that have eventually clarified the specific phenotypic identity of true multipotent CSCs. These cells when coaxed by embryonic cardiac morphogens undergo a precisely orchestrated myogenic commitment process robustly generating bona-fide functional cardiomyocytes. These data should set the path for the revival of further investigation untangling the regenerative biology of adult CSCs to harness their potential for HF prevention and treatment.
 
From: Cianflone et al.,  2018; 17(8):927-946.

Optimizing cardiac repair and regeneration through activation of the endogenous cardiac stem cell compartment

Given the aging of the Western World and declining death rates due to acute coronary syndromes, the increasing trends in the magnitude and morbidity of heart failure (HF) are predicted to continue for the foreseeable future. It is imperative to develop effective therapies for the amelioration and prevention of HF. The search for the best cell type to be used in clinical protocols of cardiac regeneration is still on. That the adult mammalian heart harbors endogenous, multipotent cardiac stem/progenitor cells (eCSCs) and that cardiomyocytes are replaced throughout adulthood represent a paradigm shift in cardiovascular biology. The presence of eCSCs supports the view that the heart can repair itself if the eCSCs can be properly stimulated. Pending a better understanding of eCSC biology, it should be possible to replace autologous cell transplantation-based myocardial regeneration protocols with an “off-the-shelf,” readily available, and effective regenerative/reparative therapy based on activation of the eCSCs in situ.

From: Nadal-Ginard B. et al., Stem Cell Research, 2014; 13(3,B):615-30.