Altered proteome biology of cardiac mitochondria under stress conditions

J Proteome Res. 2008 Jun;7(6):2204-14. doi: 10.1021/pr070371f. Epub 2008 May 17.

Abstract

Myocardial ischemia-reperfusion induces mitochondrial dysfunction and, depending upon the degree of injury, may lead to cardiac cell death. However, our ability to understand mitochondrial dysfunction has been hindered by an absence of molecular markers defining the various degrees of injury. To address this paucity of knowledge, we sought to characterize the impact of ischemic damage on mitochondrial proteome biology. We hypothesized that ischemic injury induces differential alterations in various mitochondrial subcompartments, that these proteomic changes are specific to the severity of injury, and that they are important to subsequent cellular adaptations to myocardial ischemic injury. Accordingly, an in vitro model of cardiac mitochondria injury in mice was established to examine two stress conditions: reversible injury (induced by mild calcium overload) and irreversible injury (induced by hypotonic stimuli). Both forms of injury had a drastic impact on the proteome biology of cardiac mitochondria. Altered mitochondrial function was concomitant with significant protein loss/shedding from the injured organelles. In the setting of mild calcium overload, mitochondria retained functionality despite the release of numerous proteins, and the majority of mitochondria remained intact. In contrast, hypotonic stimuli caused severe damage to mitochondrial structure and function, induced increased oxidative modification of mitochondrial proteins, and brought about detrimental changes to the subproteomes of the inner mitochondrial membrane and matrix. Using an established in vivo murine model of regional myocardial ischemic injury, we validated key observations made by the in vitro model. This preclinical investigation provides function and suborganelle location information on a repertoire of cardiac mitochondrial proteins sensitive to ischemia reperfusion stress and highlights protein clusters potentially involved in mitochondrial dysfunction in the setting of ischemic injury.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Calcium / pharmacology
  • Carrier Proteins / analysis
  • Carrier Proteins / metabolism
  • Catalase / metabolism
  • Chromatography, Liquid
  • Creatine Kinase, Mitochondrial Form / metabolism
  • Fatty Acid-Binding Proteins / metabolism
  • Hypotonic Solutions / pharmacology
  • Iron-Binding Proteins / metabolism
  • Membrane Proteins / analysis
  • Membrane Proteins / metabolism
  • Mice
  • Mice, Inbred ICR
  • Microfilament Proteins / metabolism
  • Mitochondria, Heart / drug effects
  • Mitochondria, Heart / metabolism*
  • Mitochondria, Heart / ultrastructure
  • Mitochondrial Membrane Transport Proteins
  • Mitochondrial Proteins / analysis
  • Mitochondrial Proteins / metabolism*
  • Oxidative Stress / physiology
  • Peroxiredoxins / analysis
  • Peroxiredoxins / metabolism
  • Proteome / analysis
  • Proteome / metabolism*
  • Reperfusion Injury / metabolism*
  • Reperfusion Injury / pathology
  • Repressor Proteins / metabolism
  • Reproducibility of Results
  • Superoxide Dismutase / metabolism
  • Tandem Mass Spectrometry

Substances

  • Carrier Proteins
  • Fabp4 protein, mouse
  • Fatty Acid-Binding Proteins
  • Hypotonic Solutions
  • Iron-Binding Proteins
  • Membrane Proteins
  • Microfilament Proteins
  • Mitochondrial Membrane Transport Proteins
  • Mitochondrial Proteins
  • Proteome
  • Repressor Proteins
  • Timm44 protein, mouse
  • flotillins
  • frataxin
  • prohibitin
  • moesin
  • Peroxiredoxins
  • Catalase
  • Superoxide Dismutase
  • Creatine Kinase, Mitochondrial Form
  • Calcium