Biphasic modulation of the mitochondrial electron transport chain in myocardial ischemia and reperfusion

Research output: Contribution to journalArticle

Authors

External Institution(s)

  • Ohio State University
  • National Cheng Kung University
  • Northeastern Ohio Universities College of Medicine

Details

Original languageEnglish (US)
Pages (from-to)H1410-H1422
JournalAmerican Journal of Physiology - Heart and Circulatory Physiology
Volume302
Issue number7
StatusPublished - Apr 1 2012
Peer-reviewedYes

Abstract

Mitochondrial electron transport chain (ETC) is the major source of reactive oxygen species during myocardial ischemia-reperfusion (I/R) injury. Ischemic defect and reperfusion-induced injury to ETC are critical in the disease pathogenesis of postischemic heart. The properties of ETC were investigated in an isolated heart model of global I/R. Rat hearts were subjected to ischemia for 30 min followed by reperfusion for 1 h. Studies of mitochondrial function indicated a biphasic modulation of electron transfer activity (ETA) and ETC protein expression during I/R. Analysis of ETAs in the isolated mitochondria indicated that complexes I, II, III, and IV activities were diminished after 30 min of ischemia but increased upon restoration of flow. Immunoblotting analysis and ultrastructural analysis with transmission electron microscopy further revealed marked downregulation of ETC in the ischemic heart and then upregulation of ETC upon reperfusion. No significant difference in the mRNA expression level of ETC was detected between ischemic and postischemic hearts. However, reperfusion-induced ETC biosynthesis in myocardium can be inhibited by cycloheximide, indicating the involvement of translational control. Immunoblotting analysis of tissue homogenates revealed a similar profile in peroxisome proliferator-activated receptor-γ coactivator-1α expression, suggesting its essential role as an upstream regulator in controlling ETC biosynthesis during I/R. Significant impairment caused by ischemic and postischemic injury was observed in the complexes I- III. Analysis of NADH ferricyanide reductase activity indicated that injury of flavoprotein subcomplex accounts for 50% decline of intact complex I activity from ischemic heart. Taken together, our findings provide a new insight into the molecular mechanism of I/R-induced mitochondrial dysfunction.

    Research areas

  • Protein biosynthesis, Reactive oxygen species

Citation formats

APA

Lee, H. L., Chen, C. L., Yeh, S. T., Zweier, J. L., & Chen, Y. R. (2012). Biphasic modulation of the mitochondrial electron transport chain in myocardial ischemia and reperfusion. American Journal of Physiology - Heart and Circulatory Physiology, 302(7), H1410-H1422. https://doi.org/10.1152/ajpheart.00731.2011

Harvard

Lee, HL, Chen, CL, Yeh, ST, Zweier, JL & Chen, YR 2012, 'Biphasic modulation of the mitochondrial electron transport chain in myocardial ischemia and reperfusion', American Journal of Physiology - Heart and Circulatory Physiology, vol. 302, no. 7, pp. H1410-H1422. https://doi.org/10.1152/ajpheart.00731.2011