This competitive renewal application is designed to test three new hypotheses about the role of excessive oxidative stress and calmodulin kinase II (CaMKII) in pathological responses to myocardial infarction (MI) and aldosterone (Aldo). These studies will use new genetic mouse models developed by us where the activity of mitochondrial CaMKII, oxidized CaMKII (ox-CaMKII) and methionine sulfoxide reductase A (MsrA), the enzyme that reduces and inactivates ox-CaMKII, are controlled. Each of the inter-related, but independent aims is backed by strong preliminary data.
Aim 1 Determine how Aldo and ox-CaMKII promote cardiac rupture after MI. We will determine if Aldo increases the frequency of post-MI rupture by enhancing NADPH oxidase and ox-CaMKII, and unravel a previously unknown pathway where ox-CaMKII drives myocardial matrix metalloproteinase 9 (MMP9) expression by HDAC4/5 phosphorylation and MEF2 derepression.
Aim 2 Determine the role of ox-CaMKII in myocardial hypertrophy. CaMKII contributes to myocardial hypertrophy, but the potential role of the ox-CaMKII pathway in myocardial hypertrophy is unknown. We will test the novel concept that myocardial ox-CaMKII coherently promotes transcription of matrix remodeling (in Aim 1) and hypertrophic gene programs (in Aim 2) by HDAC4/5 phosphorylation and MEF2 derepression.
Aim 3 Determine the role of ox-CaMKII in the transition from hypertrophy to heart failure. Our preliminary studies indicate that CaMKII is resident in mitochondria and that mitochondrial ox-CaMKII plays a decisive role in mitochondria membrane permeability transition pore (mPTP) opening and cell death. We predict that mitochondrial-targeted CaMKII inhibition will significantly delay and mitochondrial-targeted CaMKII over-expression will significantly hasten development of heart failure.

Public Health Relevance

Myocardial infarction (MI) is a major cause of death and suffering in the United States. Patients may die soon after MI from rupture of the heart muscle (myocardium). At present there are no highly effective treatments for myocardial rupture. Patients who survive the initial MI event are at risk developing heart failure later. Heart failure is a major cause of hospitalization and confers a high mortality that is comparable to many cancers. Our studies will test the idea that calmodulin kinase II (CaMKII) is a critical signal for causing post-MI myocardial rupture and heart failure. The goal of this work is to determine how CaMKII contributes to pathological responses to MI and explore the potential for therapeutic manipulation of the CaMKII pathway in mouse models to improve outcomes in patients who suffer MI.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL079031-08
Application #
8583335
Study Section
Cardiac Contractility, Hypertrophy, and Failure Study Section (CCHF)
Program Officer
Krull, Holly
Project Start
2004-12-01
Project End
2015-11-30
Budget Start
2013-12-01
Budget End
2014-11-30
Support Year
8
Fiscal Year
2014
Total Cost
$339,750
Indirect Cost
$114,750
Name
University of Iowa
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
062761671
City
Iowa City
State
IA
Country
United States
Zip Code
52242
Manotheepan, Ravinea; Danielsen, Tore K; Sadredini, Mani et al. (2016) Exercise training prevents ventricular tachycardia in CPVT1 due to reduced CaMKII-dependent arrhythmogenic Ca2+ release. Cardiovasc Res 111:295-306
Sommese, Leandro; Valverde, Carlos A; Blanco, Paula et al. (2016) Ryanodine receptor phosphorylation by CaMKII promotes spontaneous Ca(2+) release events in a rodent model of early stage diabetes: The arrhythmogenic substrate. Int J Cardiol 202:394-406
Mesubi, Olurotimi O; Anderson, Mark E (2016) Atrial remodelling in atrial fibrillation: CaMKII as a nodal proarrhythmic signal. Cardiovasc Res 109:542-57
Wu, Yuejin; Valdivia, Héctor H; Wehrens, Xander H T et al. (2016) A Single Protein Kinase A or Calmodulin Kinase II Site Does Not Control the Cardiac Pacemaker Ca2+ Clock. Circ Arrhythm Electrophysiol 9:e003180
Gao, Zhan; Sierra, Ana; Zhu, Zhiyong et al. (2016) Loss of ATP-Sensitive Potassium Channel Surface Expression in Heart Failure Underlies Dysregulation of Action Potential Duration and Myocardial Vulnerability to Injury. PLoS One 11:e0151337
Unudurthi, Sathya D; Wu, Xiangqiong; Qian, Lan et al. (2016) Two-Pore K+ Channel TREK-1 Regulates Sinoatrial Node Membrane Excitability. J Am Heart Assoc 5:e002865
Wu, Yuejin; Rasmussen, Tyler P; Koval, Olha M et al. (2015) The mitochondrial uniporter controls fight or flight heart rate increases. Nat Commun 6:6081
Wu, Yuejin; Rasmussen, Tyler P; Koval, Olha M et al. (2015) Corrigendum: The mitochondrial uniporter controls fight or flight heart rate increases. Nat Commun 6:7241
Anderson, Mark E (2015) Oxidant stress promotes disease by activating CaMKII. J Mol Cell Cardiol 89:160-7
Rasmussen, Tyler P; Wu, Yuejin; Joiner, Mei-ling A et al. (2015) Inhibition of MCU forces extramitochondrial adaptations governing physiological and pathological stress responses in heart. Proc Natl Acad Sci U S A 112:9129-34

Showing the most recent 10 out of 99 publications