Fe(III) distribution varies substantially within and between atherosclerotic plaques

Authors

  • H. Gustafsson,

    Corresponding author
    1. Department of Medical and Health Sciences (IMH), Division of Radiological Sciences, Linköping University, Linköping, Sweden
    2. Center for Medical Image Science and Visualization (CMIV), Linköping University, Linköping, Sweden
    • Correspondence to: Håkan Gustafsson, Ph.D., IMH/Radiation Physics, Linköping University, Linköping 581 85, Sweden. E-mail: hakan.l.gustafsson@liu.se

    Search for more papers by this author
  • M. Hallbeck,

    1. Pathology, Faculty of Health Sciences, Department of Clinical and Experimental Medicine, Linköping University, Department of Clinical Pathology, County Council of Östergötland, Linköping, Sweden
    Search for more papers by this author
  • M. Norell,

    1. Department of Medical and Health Sciences, Division of Clinical Physiology, Linköping University, Linköping, Sweden
    Search for more papers by this author
  • M. Lindgren,

    1. Department of Physics, Norwegian University of Science and Technology, Trondheim, Norway
    Search for more papers by this author
  • M. Engström,

    1. Department of Medical and Health Sciences (IMH), Division of Radiological Sciences, Linköping University, Linköping, Sweden
    2. Center for Medical Image Science and Visualization (CMIV), Linköping University, Linköping, Sweden
    Search for more papers by this author
  • A. Rosén,

    1. Department of Clinical and Experimental Medicine, Division of Cell Biology, Linköping University, Linköping, Sweden
    Search for more papers by this author
  • H. Zachrisson

    1. Department of Medical and Health Sciences, Division of Clinical Physiology, Linköping University, Linköping, Sweden
    Search for more papers by this author

Abstract

Purpose

Vulnerable atherosclerotic plaques are structurally weak and prone to rupture, presumably due to local oxidative stress. Redox active iron is linked to oxidative stress and the aim of this study was to investigate the distribution of Fe(III) in carotid plaques and its relation to vulnerability for rupture.

Methods

Atherosclerotic plaques from 10 patients (three asymptomatic and seven symptomatic) were investigated. Plaque vulnerability was classified using ultrasound and immunohistochemistry and correlated to Fe(III) measured by electron paramagnetic resonance spectroscopy.

Results

Large intra-plaque Fe(III) variations were found. Plaques from symptomatic patients had a higher Fe(III) concentration as compared with asymptomatic plaques (0.36 ± 0.21 vs. 0.06 ± 0.04 nmol Fe(III)/mg tissue, P < 0.05, in sections adjoining narrowest part of the plaques). All but one plaque from symptomatic patients showed signs of cap rupture. No plaque from asymptomatic patients showed signs of cap rupture. There was a significant increase in cap macrophages in plaques from symptomatic patients compared with asymptomatic patients (31 ± 11% vs. 2.3 ± 2.3%, P < 0.01).

Conclusion

Fe(III) distribution varies substantially within atherosclerotic plaques. Plaques from symptomatic patients had significantly higher concentrations of Fe(III), signs of cap rupture and increased cap macrophage activity. Magn Reson Med 71:885–892, 2014. © 2013 Wiley Periodicals, Inc.

Ancillary