Cardiac repair

However, new insights into the mechanisms of cardiac repair have provided evidence that the adult heart can at least partially repair injury and that vasculogenesis may not occur solely during embryonic development. These insights, in turn, have sparked strong interest in the field of stem cell therapy [2, 3]. Prompted by evidence that adult bone marrow harbors a reservoir of plastic cells [4], animal experiments have generated evidence... 

The field of stem cell therapy has benefited from the work of numerous basic and clinical scientists whose studies have greatly improved our understanding of the processes involved in cardiac repair and neovascularization. The creation of new blood vessels (neovascularization) requires the formation of new mature endothelial cells. In this process, the new... 

Further evidence for a dynamic cardiac renewal process in the adult heart comes from the recent identification of a novel population of early tissue-committed stem cells that may be part of a group of circulating progenitor cells involved in cardiac repair [40]. 

Thus far, the most important bone marrow sub-types utilized for cardiac repair have been MSCs, EPCs, or, alternatively, the whole ABMMNC fraction. Newly described bone marrow cell subtypes with therapeutic potential are discussed below. 

The use of skeletal myoblasts for cardiac repair originated from earlier attempts where fetal cardio-myocytes were used. When injected into the border... 

The concept of cell-based cardiac repair has gained a large amount of focus over the past decade and is discussed in previous chapters. This modality will only become more widely used in the future. There have been several studies utilizing skeletal muscle in ischemic cardiomyopathy [37-39]. No conclusions can be made but there are some indications of improvement in function but arrhythmias have been a concern. 

Murry CE, Eield LJ, Menasche P. Cell-based cardiac repair reflections at the 10-year point. Circulation. Nov 15 2005 112(20) 3174-3183. 

Cell-based cardiac repair in 2006 the continued questions... 

In summary, the future is bright, the potential is great, and the treatment options are increasing, However, even as the field progresses, we have a responsibility to promise patients (and the press) only what we can deliver, that is, to tell the truth about cardiac repair. At present, it is not a panacea. Functional improvements are modest and even then the best results are not yet validated in randomized controlled trials. Cell therapy is however a new alternative that warrants much further exploration. 

Dimmeler S, Zeiher AM, Schneider MD. Unchain my heart the scientific foundations of cardiac repair. J Clin Invest 2005 ... 

Knowlton KU, Chien KR. Inflammatory pathways and cardiac repair The affliction of infarction. Nat Med 1999 5 1122-1123. 

Boyle AJ, Schulman SP, Hare JM. Is stem cell therapy ready for patients Stem cell therapy for cardiac repair ready for the next step. Circulation 2006 114 339-52. 

In summary, there are many stem cell types that have the potential for cardiac repair, but more sophisticated cell culture and TE approaches need to be developed. In addition, the main obstacle influencing cell therapeutic efflcacy is the high death rate of donor stem cells after transplantation. Fabrication of biomaterial scaffolds with suitable nanostructure could be a feasible strategy for optimizing stem cell therapy for cardiac regeneration. 

Transplantation of adult bone marrow-derived mesenchymal stem cells has been proposed as a strategy for cardiac repair... 

Orlic D (2005). BM stem cells and cardiac repair where do we stand in 2004 Cyto-ther. 7 3-15. 

Bock-Marquette, I., et al. Thymosin 34 activates integrin-linked kinase and promotes cardiac cell migration and cardiac repair. Science 2004, 432, 466 72. But see also more recent encouraging results Smart, N., et al. Thymosin 34 induces adult epicardial progenitor mobilization and neovascularization. Nature 2007,... 

Castellano, D., Blanes, M., Marco, B., Cerrada, I., Ruiz-Sauri, A., Pelacho, B., Arana, M., Montero, J.A., Camhra, V., Prosper, F., Sepulveda, P., 2014. A comparison of electrospun polymers reveals poly(3-hydroxybutyrate) fiber as a superior scaffold for cardiac repair. Stem Cells and Development 23 (13), 1479—1490. 

Scaffolds have been used successfully in cardiac repair, especially in conjunction with stem cells. A scaffold seeded with stem cells may be implanted directly into a heart valve, roughly at the site where a cardiac infarction has occurred. The scaffold then directs the growing cells toward the injured area and facilitates regeneration of damaged tissue. 

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