Targeted intracellular accumulation of macrophage migration inhibitory factor in the reperfused heart mediates cardioprotection

Thromb Haemost. 2016 Jan;115(1):200-12. doi: 10.1160/TH15-05-0436. Epub 2015 Aug 27.

Abstract

S-nitrosation of macrophage migration inhibitory factor (MIF) has been shown to be cytoprotective in myocardial ischaemia/reperfusion (I/R) injury. Since the exact mechanism of action is unknown, we here characterise the cardioprotective effects of targeted intracellular accumulation of MIF in myocardial I/R injury. We used different in vivo, ex vivo and in vitro models of myocardial I/R and hypoxia/reoxygenation (H/R) injury to determine MIF levels by immunoblots and ELISA in different phases of reperfusion and reoxygenation, respectively. We discovered a rapid decrease of cardiac MIF that was specific to the early phase of reperfusion. Posttranslational modification of MIF via S-nitrosation--proofed by a modified version of the Biotin Switch Assay--prevented this rapid decrease, leading to a targeted intracellular accumulation of MIF in the early phase of reperfusion. Intracellular MIF accumulation preserved the intracellular ability of MIF to reduce oxidative stress as shown by hydrogen peroxide and aconitase activity measurements. Infarct size measurements by TTC staining showed an overall enhanced cardioprotective effect of this protein by reduction of reperfusion injury. In summary, we have unravelled a novel mechanism of MIF-mediated cardioprotection. Targeted intracellular accumulation of MIF by S-nitrosation may offer a novel therapeutic approach in the treatment of myocardial I/R-injury.

Keywords: Cardioprotection; macrophage migration inhibitory factor; myocardial ischaemia/reperfusion injury; oxidative stress.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aconitate Hydratase / metabolism
  • Animals
  • Cell Line
  • Disease Models, Animal
  • Hydrogen Peroxide / metabolism
  • Intramolecular Oxidoreductases / deficiency
  • Intramolecular Oxidoreductases / genetics
  • Intramolecular Oxidoreductases / metabolism*
  • Macrophage Migration-Inhibitory Factors / deficiency
  • Macrophage Migration-Inhibitory Factors / genetics
  • Macrophage Migration-Inhibitory Factors / metabolism*
  • Male
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Myocardial Infarction / genetics
  • Myocardial Infarction / metabolism
  • Myocardial Infarction / pathology
  • Myocardial Infarction / prevention & control*
  • Myocardial Reperfusion Injury / genetics
  • Myocardial Reperfusion Injury / metabolism
  • Myocardial Reperfusion Injury / pathology
  • Myocardial Reperfusion Injury / prevention & control*
  • Myocytes, Cardiac / metabolism*
  • Myocytes, Cardiac / pathology
  • Nitrosation
  • Oxidative Stress
  • Protein Processing, Post-Translational
  • Time Factors

Substances

  • Macrophage Migration-Inhibitory Factors
  • Hydrogen Peroxide
  • Aconitate Hydratase
  • Intramolecular Oxidoreductases
  • Mif protein, mouse