Heart disease is a major cause of morbidity and mortality, much of it due to ischemic injury. Mitophagy and biogenesis (mitochondrial turnover) are essential for ischemia tolerance and appropriate recovery during reperfusion. Factors that affect mitochondrial turnover include age, sex, time of day, comorbid conditions such as age and metabolic syndrome, nutritional status, exercise, and a long list of drugs and natural products. The overarching hypothesis is that monitoring mitochondrial turnover will allow us to infer a patient?s response to ischemic stress, and that normalizing turnover will improve outcome. In this proposal we develop tools to measure mitochondrial turnover (Aim I), define the regulation of mitochondrial turnover (Aim II), and leverage the knowledge gained to monitor mitochondrial turnover in the human heart during cardiopulmonary bypass (Aim III). Additionally we will measure mitochondrial function in endomyocardial biopsies of heart transplant patients, where it will be possible to relate mitochondrial function to cardiac contractility.
In Aim I we will use our novel MitoTimer mice and organelle flow cytometry to develop a proteomic signature of mitophagy and biogenesis. The protein profiles will be used to create a mass spectrometry assay (multiple reaction monitoring, MRM) to infer mitochondrial turnover in tissue extracts including human heart biopsies. This index of mitophagy and biogenesis will be used to assess mitochondrial turnover in rodents in Aim I and in human heart biopsies in Aim III.
In Aim II, we will delineate the regulation of mitophagy by PINK1, Parkin, and optineurin; and the regulation of mitochondrial biogenesis by PGC-1alpha, PARIS, and translational machinery. We have established polysome profiling to interrogate translational control of mitochondrial biogenesis.
In Aim III we will use paired atrial biopsies (before and after cardiopulmonary bypass) to characterize mitophagy and biogenesis in the human heart?s response to ischemic stress; we will use paired atrial and ventricular biopsies to gain much-needed information about the differences in mitochondrial function and cardiac proteome; and we will correlate mitochondrial respirometry, mtDNA damage, and MRM assays of mitochondrial turnover to correlate with clinical parameters, specifically postoperative atrial fibrillation. These studies will establish the molecular signatures of appropriate mitochondrial turnover during cardiac surgery, providing markers of target engagement that will position us to evaluate therapeutic interventions. Importantly, understanding this pathway will reveal new therapeutic targets that regulate mitochondrial turnover and influence function of the human heart recovering from ischemia.

Public Health Relevance

This study will develop a mass spectrometry assay to measure mitochondrial biogenesis and elimination, and will apply that to human heart biopsies obtained during cardiac surgery. The study will also define the molecular regulation of mitophagy and biogenesis in animal models and correlation in human heart.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL132075-02
Application #
9397565
Study Section
Myocardial Ischemia and Metabolism Study Section (MIM)
Program Officer
Schwartz, Lisa
Project Start
2016-12-15
Project End
2020-11-30
Budget Start
2017-12-01
Budget End
2018-11-30
Support Year
2
Fiscal Year
2018
Total Cost
Indirect Cost
Name
Cedars-Sinai Medical Center
Department
Type
DUNS #
075307785
City
Los Angeles
State
CA
Country
United States
Zip Code
90048
Elliott, Eric I; Miller, Alexis N; Banoth, Balaji et al. (2018) Cutting Edge: Mitochondrial Assembly of the NLRP3 Inflammasome Complex Is Initiated at Priming. J Immunol 200:3047-3052
Parker, Sarah J; Stotland, Aleksandr; MacFarlane, Elena et al. (2018) Proteomics reveals Rictor as a noncanonical TGF-? signaling target during aneurysm progression in Marfan mice. Am J Physiol Heart Circ Physiol 315:H1112-H1126
Aminzadeh, Mark A; Rogers, Russell G; Fournier, Mario et al. (2018) Exosome-Mediated Benefits of Cell Therapy in Mouse and Human Models of Duchenne Muscular Dystrophy. Stem Cell Reports 10:942-955
Fu, Qin; Kowalski, Michael P; Mastali, Mitra et al. (2018) Highly Reproducible Automated Proteomics Sample Preparation Workflow for Quantitative Mass Spectrometry. J Proteome Res 17:420-428
Lindsey, Merry L; Bolli, Roberto; Canty Jr, John M et al. (2018) Guidelines for experimental models of myocardial ischemia and infarction. Am J Physiol Heart Circ Physiol 314:H812-H838
Aebersold, Ruedi; Agar, Jeffrey N; Amster, I Jonathan et al. (2018) How many human proteoforms are there? Nat Chem Biol 14:206-214
Coronado, Michael; Fajardo, Giovanni; Nguyen, Kim et al. (2018) Physiological Mitochondrial Fragmentation Is a Normal Cardiac Adaptation to Increased Energy Demand. Circ Res 122:282-295
Stastna, Miroslava; Thomas, Amandine; Germano, Juliana et al. (2018) Dynamic Proteomic and miRNA Analysis of Polysomes from Isolated Mouse Heart After Langendorff Perfusion. J Vis Exp :
Mishra, Rajeev; Haldar, Subhash; Placencio, Veronica et al. (2018) Stromal epigenetic alterations drive metabolic and neuroendocrine prostate cancer reprogramming. J Clin Invest 128:4472-4484
Crupi, Annunziata N; Nunnelee, Jordan S; Taylor, David J et al. (2018) Oxidative muscles have better mitochondrial homeostasis than glycolytic muscles throughout life and maintain mitochondrial function during aging. Aging (Albany NY) 10:3327-3352

Showing the most recent 10 out of 25 publications