This proposal utilizes the isolated perfused rabbit heart model of global ischemia to characterize the molecular events leading to cell death during ischemia and reperfusion. Biochemical and histological analysis are coupled to cell-free assays designed to evaluate protein-protein interactions. Myocardial ischemia is accompanied by ionic shifts, free radical production, and a commitment to cell death by apoptosis and necrosis. Proteolysis is one mechanism to irreversibly commit the cell to a death program. Bid is a member of the pro-apoptotic BH3-only subset of the Bc1-2 family. Bid is activated by proteolysis to translocate to the mitochondria to direct cytochrome c release. Loss of cytochrome c impairs mitochondrial respiration, may favor superoxide production, and may contribute to delayed caspase activation. Bid can be cleaved and activated by caspase-8, calpain, and lysosomal proteases. We have evidence that Bid is cleaved by calpain during myocardial ischemia, and propose to determine whether this is of physiological significance. ARC (Apoptosis Repressor with CARD Domain) is an anti-apoptotic molecule expressed at high levels in the heart. ARC has been shown to inhibit caspase-8 and prevent cytochrome c release; we find that ARC prevents cytochrome c release mediated by cleaved active Bid, suggesting a direct interaction. We propose to examine the interaction between ARC and Bid. We also find that ARC is susceptible to proteolysis during ischemia, and find that calpain is one protease that is able to cleave and inactivate ARC. We propose to examine the physiological significance of ARC proteolysis in ischemia. In order to establish more useful tools for studying the molecular events in ischemia, we propose to develop the methodology for TAT protein transduction in the isolated heart model.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL060590-06
Application #
6623795
Study Section
Cardiovascular and Pulmonary Research A Study Section (CVA)
Program Officer
Liang, Isabella Y
Project Start
1998-09-01
Project End
2007-08-31
Budget Start
2003-09-01
Budget End
2004-08-31
Support Year
6
Fiscal Year
2003
Total Cost
$324,100
Indirect Cost
Name
Scripps Research Institute
Department
Type
DUNS #
781613492
City
La Jolla
State
CA
Country
United States
Zip Code
92037
Gottlieb, Roberta A; Stotland, Aleksandr (2015) MitoTimer: a novel protein for monitoring mitochondrial turnover in the heart. J Mol Med (Berl) 93:271-8
Andres, Allen M; Stotland, Aleksandr; Queliconi, Bruno B et al. (2015) A time to reap, a time to sow: mitophagy and biogenesis in cardiac pathophysiology. J Mol Cell Cardiol 78:62-72
Andres, Allen M; Hernandez, Genaro; Lee, Pamela et al. (2014) Mitophagy is required for acute cardioprotection by simvastatin. Antioxid Redox Signal 21:1960-73
Pepe, Salvatore; Mentzer Jr, Robert M; Gottlieb, Roberta A (2014) Cell-permeable protein therapy for complex I dysfunction. J Bioenerg Biomembr 46:337-45
Mentzer Jr, Robert M; Wider, Joseph; Perry, Cynthia N et al. (2014) Reduction of infarct size by the therapeutic protein TAT-Ndi1 in vivo. J Cardiovasc Pharmacol Ther 19:315-20
Hernandez, Genaro; Thornton, Christine; Stotland, Aleksandr et al. (2013) MitoTimer: a novel tool for monitoring mitochondrial turnover. Autophagy 9:1852-61
Jahania, Salik M; Sengstock, David; Vaitkevicius, Peter et al. (2013) Activation of the homeostatic intracellular repair response during cardiac surgery. J Am Coll Surg 216:719-26; discussion 726-9
Gottlieb, Roberta A; Mentzer Jr, Robert M (2013) Autophagy: an affair of the heart. Heart Fail Rev 18:575-84
Klionsky, Daniel J (see original citation for additional authors) (2012) Guidelines for the use and interpretation of assays for monitoring autophagy. Autophagy 8:445-544
Giricz, Zoltan; Mentzer Jr, Robert M; Gottlieb, Roberta A (2012) Autophagy, myocardial protection, and the metabolic syndrome. J Cardiovasc Pharmacol 60:125-32

Showing the most recent 10 out of 56 publications