Currently, we have little understanding of the etiology of myocardial aging. Rarely, studies in animals and humans have considered aging as an independent process and time as the major cause of the aging myopathy. Only occasionally cardiac aging in humans has been characterized independently from concomitant pathologic states. Aging has been interpreted as a variable, which cooperates with a variety of diseases, to define the old, poorly functional heart. This Program Project Grant (PPG) aims at the: a) Definition of myocardial aging;b) Identification of the determinants of the cardiac senescent phenotype;and c) Recognition whether the aging myopathy conditions health and life span. The major hypothesis to be tested is that aging of cardiac stem cells (CSCs) affects the size and properties of the myocyte, vascular, and fibroblast progeny which, in turn, conditions the structure and function of the heart. Aged CSCs may generate a smaller number of senescent myocytes with defects in electrical and mechanical behavior, and a larger number of fibroblasts which, together, underlie diastolic dysfunction and the old cardiac phenotype. This PPG has five objectives: a) To determine whether the adult heart is a self-autonomous organ regulated by the orderly organization and growth of CSCs;b) To determine whether telomeric shortening in CSCs with aging leads to time-dependent changes in the growth properties of CSCs and characteristics of the differentiated progeny;c) To determine whether old CSCs with short telomeres generate functionally-defective myocytes together with enhanced formation of fibroblasts;d) To determine whether accumulation of fibroblasts and myocytes with impaired contractile performance promotes diastolic dysfunction, typically present in the senescent heart;and e) To determine whether strategies preventing the aging myopathy, or reversing myocardial aging can be developed to extend health and life span in the elderly. The common theme of this PPG is understanding the control of CSC growth and commitment, the etiology of CSC senescence and death, and the impact that old CSCs have on the properties of the differentiated progeny The telomere-telomerase axis is viewed as the key regulator of CSC replication, senescence and death, conditioning myocyte, coronary vasculature, and organ aging. Alterations in the turnover rate of cardiomyocytes, vascular cells, and fibroblasts define the aging myopathy. CSCs with preserved function are present in the old heart, and repopulating protocols with CSCs possessing intact telomeres may replace defective myocytes with new, mechanically efficient cells, and restore the coronary vasculature and microvasculature reversing the senescent phenotype, ultimately, prolonging health and life span of the organ and organism. To fulfill these objectives, the role of CSCs in myocardial aging of small (Projects 1 and 2) and large (Project 3) animals and humans (Project 4) will be investigated in an integrated manner to identify the variables that lead to ventricular dysfunction in the old heart.

Public Health Relevance

The recognition that defects in CSC function determine organ aging and heart failure offers the unique opportunity to develop novel strategies for the management of the senescent cardiac phenotype, potentially prolonging health and life span in the elderly.

Agency
National Institute of Health (NIH)
Institute
National Institute on Aging (NIA)
Type
Research Program Projects (P01)
Project #
1P01AG043353-01
Application #
8415033
Study Section
Special Emphasis Panel (ZAG1-ZIJ-7 (01))
Program Officer
Kohanski, Ronald A
Project Start
2012-12-01
Project End
2017-11-30
Budget Start
2012-12-01
Budget End
2013-11-30
Support Year
1
Fiscal Year
2013
Total Cost
$2,299,561
Indirect Cost
$755,645
Name
Brigham and Women's Hospital
Department
Type
DUNS #
030811269
City
Boston
State
MA
Country
United States
Zip Code
02115
Borghetti, Giulia; Eisenberg, Carol A; Signore, Sergio et al. (2018) Notch signaling modulates the electrical behavior of cardiomyocytes. Am J Physiol Heart Circ Physiol 314:H68-H81
Wysoczynski, Marcin; Guo, Yiru; Moore 4th, Joseph B et al. (2017) Myocardial Reparative Properties of Cardiac Mesenchymal Cells Isolated on the Basis of Adherence. J Am Coll Cardiol 69:1824-1838
Meo, Marianna; Meste, Olivier; Signore, Sergio et al. (2016) Reduction in Kv Current Enhances the Temporal Dispersion of the Action Potential in Diabetic Myocytes: Insights From a Novel Repolarization Algorithm. J Am Heart Assoc 5:
Sorrentino, Andrea; Signore, Sergio; Qanud, Khaled et al. (2016) Myocyte repolarization modulates myocardial function in aging dogs. Am J Physiol Heart Circ Physiol 310:H873-90
Signore, Sergio; Sorrentino, Andrea; Borghetti, Giulia et al. (2015) Late Na(+) current and protracted electrical recovery are critical determinants of the aging myopathy. Nat Commun 6:8803
Moccetti, Tiziano; Leri, Annarosa; Goichberg, Polina et al. (2015) A Novel Class of Human Cardiac Stem Cells. Cardiol Rev 23:189-200
Leri, Annarosa; Rota, Marcello; Pasqualini, Francesco S et al. (2015) Origin of cardiomyocytes in the adult heart. Circ Res 116:150-66
Iso, Yoshitaka; Rao, Krithika S; Poole, Charla N et al. (2014) Priming with ligands secreted by human stromal progenitor cells promotes grafts of cardiac stem/progenitor cells after myocardial infarction. Stem Cells 32:674-83
Goichberg, Polina; Chang, Jerway; Liao, Ronglih et al. (2014) Cardiac stem cells: biology and clinical applications. Antioxid Redox Signal 21:2002-17
D'Amario, Domenico; Leone, Antonio M; Iaconelli, Antonio et al. (2014) Growth properties of cardiac stem cells are a novel biomarker of patients' outcome after coronary bypass surgery. Circulation 129:157-72

Showing the most recent 10 out of 25 publications