The myocardium possesses an inherent capacity for cellular replacement, yet this reparative process is inadequate to cope with acute injury or chronic stress. Remarkable advances are evident in the use of donated stem cell populations or expression of paracrine factors (or both) to enhance myocardial repair, but efficacy of adoptively transferred cells to generate new myocardium remains modest. Moreover, several studies indicate that repair stems predominantly from recruitment of endogenous cells activated by cellular or molecular therapeutic interventions. The overarching premise of this program is that endogenous myocardial reparative mechanisms become compromised by pathologic stimuli leading to a downward spiral of cardiac insufficiency linked to inadequate cellular replacement. Therefore, functional restoration of myocardial repair will inevitably require deciphering the molecular signaling that impairs cellular replacement and healing. Project 1 (Sussman) examines the role of extracellular matrix. Project 2 (Heller Brown) focuses upon G-protein coupled receptor signaling. Project 3 (Glembotski) is concerned with secretion / cardiokine synthesis, and Project 4 (Gustafsson) delineases the role of mitochondrial function in the regenerative process. Relieving pathologic impediments to cellular replacement will increase formation of functional myocardium and improve hemodynamic performance. Concurrent enhancement therapies to potentiate healing can then benefit from improved endogenous functional repair, leading to more effective compensation of the heart to pathologic stress. Pathological signals that impair survival, proliferation, migration, commitment, or integration of endogenous replacement cells into the stressed myocardium need to be defined, mitigated, and optimally reversed in order to restore myocardial repair. Projects in this program will demonstrate molecular mechanisms responsible for loss of reparative capacity that create nonpermissive conditions for expansion or retention of cardiogenic cells. The goal of this program will be to delineate these deleterious signaling mechanisms and determine how they can be overcome to restore endogenous cellular repair processes that heal the damaged heart.

Public Health Relevance

The possibility of regenerative medicine for treatment of heart disease is now being realized in early clinical studies, but the greatest limitation to efficient myocardial regeneration is the poor functional performance of the stem cell population. To overcome this roadblock, the molecular mechanisms that hamper myocardial healing need to be defined and manipulated in order to maximize the reparative potential of the heart. (End of Abstract)

National Institute of Health (NIH)
National Heart, Lung, and Blood Institute (NHLBI)
Research Program Projects (P01)
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Heart, Lung, and Blood Initial Review Group (HLBP)
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Wong, Renee P
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San Diego State University
Schools of Arts and Sciences
San Diego
United States
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Khan, Mohsin; Mohsin, Sadia; Toko, Haruhiro et al. (2014) Cardiac progenitor cells engineered with *ARKct have enhanced *-adrenergic tolerance. Mol Ther 22:178-85
Siddiqi, Sailay; Sussman, Mark A (2014) The heart: mostly postmitotic or mostly premitotic? Myocyte cell cycle, senescence, and quiescence. Can J Cardiol 30:1270-8
Hammerling, Babette C; Gustafsson, Åsa B (2014) Mitochondrial quality control in the myocardium: cooperation between protein degradation and mitophagy. J Mol Cell Cardiol 75:122-30
Kubli, Dieter A; Gustafsson, Asa B (2014) Cardiomyocyte health: adapting to metabolic changes through autophagy. Trends Endocrinol Metab 25:156-64
Mohsin, Sadia; Wu, Joseph C; Sussman, Mark A (2014) Predicting the future with stem cells. Circulation 129:136-8
Hariharan, Nirmala; Sussman, Mark A (2014) Stressing on the nucleolus in cardiovascular disease. Biochim Biophys Acta 1842:798-801
Völkers, Mirko; Doroudgar, Shirin; Nguyen, Nathalie et al. (2014) PRAS40 prevents development of diabetic cardiomyopathy and improves hepatic insulin sensitivity in obesity. EMBO Mol Med 6:57-65
Anderson, Mark E; Goldhaber, Joshua; Houser, Steven R et al. (2014) Embryonic stem cell-derived cardiac myocytes are not ready for human trials. Circ Res 115:335-8
Quijada, Pearl; Sussman, Mark A (2014) Making it stick: chasing the optimal stem cells for cardiac regeneration. Expert Rev Cardiovasc Ther 12:1275-88
Hariharan, Nirmala; Sussman, Mark A (2014) Pin1: a molecular orchestrator in the heart. Trends Cardiovasc Med 24:256-62

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