Heart disease is unsurpassed as the greatest noninfectious health hazard ever to confront the human race. It is estimated that five million Americans have heart failure, a syndrome with 5-year mortality of ?50%7. For some years, heart failure has remained a leading cause of death in industrialized nations, and the epidemic is rapidly expanding to include the developing world. Accordingly, heart failure, the end-result of pathological cardiac remodeling, is responsible for a huge societal burden of morbidity, mortality, and cost. Stress-induced hypertrophic growth of the myocardium is an integral step in the pathogenesis of many forms of heart failure. This hypertrophic growth process is complex, involving more than just increases in myocyte size and heightened sarcomeric organization. Rather, a shift toward glycolytic metabolism, alterations in Ca2+ storage and handling, changes in contractility, and reactivation of a fetal gene program are seen18. Importantly, some evidence suggests that suppression of pathological cardiac hypertrophy per se is a viable target for therapeutic intervention17, 19. Indeed, preclinical studies have shown that attenuation of load-induced hypertrophy is well tolerated, and ventricular dilation and decompensation do not occur17, 19, and 20. Correlative studies in heart disease patients support this contention21. To pursue suppression of pathological cardiac hypertrophy as a therapeutic intervention, studies to define proximal triggers are required. FoxO transcription factors, two isoforms of which are expressed at high levels in cardiomyocytes (FoxO1, FoxO3) govern a wide range of key molecular and cellular events, including responses to stress, cell viability, cell-cycle progressio, protein degradation and metabolic control8. Recently, we uncovered two novel, previously unappreciated pathways governed by FoxO1 which participate importantly in cardiac growth and function: a) FoxO1-dependent control of Vcam1 expression, and b) FoxO1-dependent control of intracellular thyroid hormone homeostasis. Studies laid out here are significant in that they probe mechanisms which are previously unrecognized and for which we have strong evidence of pathophysiological relevance. Additional benefits from the proposed work will accrue to the fields of FoxO biology and cardiac remodeling, as this work is expected to enable subsequent thinking and research, allowing us and others to build on a growing body of knowledge. Benefit will also accrue to other areas, such as cell adhesion molecules, thyroid hormone biology, intracellular deiodinases, and FoxO-dependent transcription. For all these reasons, work proposed here is highly significant and expected to provide concrete benefit in decreasing disease-related morbidity and mortality. As such, this work is consistent with NIH's mission to protect and improve health.

Public Health Relevance

Heart attack - myocardial injury from ischemia followed by reperfusion - is a leading cause of death. Yet, we have no therapies whatsoever targeting the reperfusion injury component of the process, even though it accounts for 50% of the pathological response. We propose to dissect two novel pathways downstream of the transcription factor Fox01, which preliminary evidence suggests contribute significantly to the maladaptive response and raise the prospect of therapeutic targeting of these novel pathways for clinical benefit.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL126012-04
Application #
9650628
Study Section
Myocardial Ischemia and Metabolism Study Section (MIM)
Program Officer
Adhikari, Bishow B
Project Start
2016-04-01
Project End
2020-02-29
Budget Start
2019-03-01
Budget End
2020-02-29
Support Year
4
Fiscal Year
2019
Total Cost
Indirect Cost
Name
University of Texas Sw Medical Center Dallas
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
800771545
City
Dallas
State
TX
Country
United States
Zip Code
75390
Cao, Dian J; Schiattarella, Gabriele G; Villalobos, Elisa et al. (2018) Cytosolic DNA Sensing Promotes Macrophage Transformation and Governs Myocardial Ischemic Injury. Circulation 137:2613-2634
Bi, Xukun; Zhang, Guangyu; Wang, Xiaoding et al. (2018) Endoplasmic Reticulum Chaperone GRP78 Protects Heart From Ischemia/Reperfusion Injury Through Akt Activation. Circ Res 122:1545-1554
Parra, Valentina; Altamirano, Francisco; Hernández-Fuentes, Carolina P et al. (2018) Down Syndrome Critical Region 1 Gene, Rcan1, Helps Maintain a More Fused Mitochondrial Network. Circ Res 122:e20-e33
Eschenhagen, Thomas; Bolli, Roberto; Braun, Thomas et al. (2017) Cardiomyocyte Regeneration: A Consensus Statement. Circulation 136:680-686
Tong, Carl W; Madhur, Meena S; Rzeszut, Anne K et al. (2017) Status of Early-Career Academic Cardiology: A Global Perspective. J Am Coll Cardiol 70:2290-2303
Tong, Dan; Hill, Joseph A (2017) Spermidine Promotes Cardioprotective Autophagy. Circ Res 120:1229-1231
Deng, Yingfeng; Wang, Zhao V; Gordillo, Ruth et al. (2017) An adipo-biliary-uridine axis that regulates energy homeostasis. Science 355:
Schiattarella, Gabriele G; Hill, Theodore M; Hill, Joseph A (2017) Is Load-Induced Ventricular Hypertrophy Ever Compensatory? Circulation 136:1273-1275
Cho, Geoffrey W; Altamirano, Francisco; Hill, Joseph A (2016) Chronic heart failure: Ca(2+), catabolism, and catastrophic cell death. Biochim Biophys Acta 1862:763-777
Kim, Soo Young; Morales, Cyndi R; Gillette, Thomas G et al. (2016) Epigenetic regulation in heart failure. Curr Opin Cardiol 31:255-65

Showing the most recent 10 out of 12 publications