title: Assessment of inflammation with a very small iron-oxide particle in a murine model of reperfused myocardial infarction.
abstract: OBJECTIVE
  To investigate a very small iron-oxide particle (VSOP) in a mouse model of acute ischemia-reperfusion to access the mechanism of such particles in areas of myocardial inflammation.
  
  
  METHODS
  Animals were injected with VSOP at several time points, in a mouse model of acute myocardial infarction (MI), before and after MI. MRI was used to localize areas of VSOP enhancement, evaluate VSOP areas extension, and determine the related T2* values. Histology, electron microscopy, macrophage counting, and Evan's Blue staining were also performed.
  
  
  RESULTS
  We found that areas of VSOP uptake decreased from 1 to 8 days post-MI while the related T2* values increased. T2* and VSOP areas, defined from MRI data, correlated well between 1 and 3 days post-MI but not at 7 days after injection. Histological analysis and electron microscopy showed colocalization of macrophages with areas of VSOP staining. However, there was no correlation between number of macrophages and the extension of the VSOP areas achieved by MR. We found that only areas of increased permeability (assessed by Evan's Blue staining) showed colocalization of macrophages and VSOP uptake.
  
  
  CONCLUSIONS
  This study demonstrates that VSOP allows the assessment of myocardial inflammation associated with increased permeability during infarct healing in a mouse model of ischemia-reperfusion.
authors.affiliation: King's College London British Heart Foundation Centre of Excellence, Cardiovascular Division, King's College London, London, United Kingdom; King's College London British Heart Foundation Centre of Excellence, Division of Imaging Sciences and Biomedical Engineering, King's College London, London, United Kingdom.
authors.forename: Andrea
authors.initials: A
authors.lastname: Protti
authors.forename: Xuebin
authors.initials: X
authors.lastname: Dong
authors.forename: Marcelo E
authors.initials: ME
authors.lastname: Andia
authors.forename: Bin
authors.initials: B
authors.lastname: Yu
authors.forename: Kate
authors.initials: K
authors.lastname: Dokukina
authors.forename: Sanjay
authors.initials: S
authors.lastname: Chaubey
authors.forename: Alkystis
authors.initials: A
authors.lastname: Phinikaridou
authors.forename: Gema
authors.initials: G
authors.lastname: Vizcay-Barrena
authors.forename: Matthias
authors.initials: M
authors.lastname: Taupitz
authors.forename: Rene M
authors.initials: RM
authors.lastname: Botnar
authors.forename: Ajay M
authors.initials: AM
authors.lastname: Shah
mesh_terms: D000818:Animals; D003287:Contrast Media; D004195:Disease Models, Animal; D005260:Female; D005290:Ferric Compounds / Q000494:pharmacology*; D007249:Inflammation / Q000473:pathology; D007275:Injections, Intravenous; D008279:Magnetic Resonance Imaging / Q000379:methods*; D051379:Mice; D008810:Mice, Inbred C57BL; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D015425:Myocardial Reperfusion / Q000379:methods*; D011897:Random Allocation; D012016:Reference Values; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media; D005290:Ferric Compounds; C000499:ferric oxide
keywords: MRI; inflammation; iron particles; myocardial infarction