Molecular Imaging (Nov 2012)

Temporal Changes in Phosphatidylserine Expression and Glucose Metabolism after Myocardial Infarction: An in Vivo Imaging Study in Mice

  • Sebastian Lehner,
  • Andrei Todica,
  • Stefan Brunner,
  • Christopher Uebleis,
  • Hao Wang,
  • Carmen Wängler,
  • Nadja Herbach,
  • Tanja Herrler,
  • Guido Böning,
  • Rüdiger Paul Laubender,
  • Paul Cumming,
  • Ralf Schirrmacher,
  • Wolfgang Franz,
  • Marcus Hacker

DOI
https://doi.org/10.2310/7290.2012.00010
Journal volume & issue
Vol. 11

Abstract

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Positron emission tomography (PET) for in vivo monitoring of phosphatidylserine externalization and glucose metabolism can potentially provide early predictors of outcome of cardioprotective therapies after myocardial infarction. We performed serial [ 68 Ga]annexin A5 PET (annexin-PET) and [ 18 F]fluorodeoxyglucose PET (FDG-PET) after myocardial infarction to determine the time of peak phosphatidylserine externalization in relation to impaired glucose metabolism in infracted tissue. Annexin- and FDG-PET recordings were obtained in female (C57BL6/N) mice on days 1 to 4 after ligation of the left anterior descending (LAD) artery. [ 68 Ga]annexin A5 uptake (%ID/g) in the LAD artery territory increased from 1.7 ± 1.1 on day 1 to 5.0 ± 3.3 on day 2 and then declined to 2.0 ± 1.4 on day 3 (p = .047 vs day 2) and 1.6 ± 1.4 on day 4 ( p = .014 vs day 2). These results matched apoptosis rates as estimated by autoradiography and fluorescein staining. FDG uptake (%ID/g) declined from 28 ± 14 on day 1 to 14 ± 3.5 on day 4 ( p < .0001 vs day 1). Whereas FDG-PET revealed continuous loss of cell viability after permanent LAD artery occlusion, annexin-PET indicated peak phosphatidylserine expression at day 2, which might be the optimal time point for therapy monitoring.