Endogenous Annexin-A1 Regulates Haematopoietic Stem Cell Mobilisation and Inflammatory Response Post Myocardial Infarction in Mice In Vivo Academic Article uri icon


  • Endogenous anti-inflammatory annexin-A1 (ANX-A1) plays an important role in preserving left ventricular (LV) viability and function after ischaemic insults in vitro, but its long-term cardioprotective actions in vivo are largely unknown. We tested the hypothesis that ANX-A1-deficiency exaggerates inflammation, haematopoietic stem progenitor cell (HSPC) activity and LV remodelling in response to myocardial ischaemia in vivo. Adult ANX - A1 -/- mice subjected to coronary artery occlusion exhibited increased infarct size and LV macrophage content after 24-48 h reperfusion compared with wildtype (WT) counterparts. In addition, ANX - A1 -/- mice exhibited greater expansion of HSPCs and altered pattern of HSPC mobilisation 8 days post-myocardial infarction, with increased circulating neutrophils and platelets, consistent with increased cardiac inflammation as a result of increased myeloid invading injured myocardium in response to MI. Furthermore, ANX - A1 -/- mice exhibited significantly increased expression of LV pro-inflammatory and pro-fibrotic genes and collagen deposition after MI compared to WT counterparts. ANX-A1-deficiency increased cardiac necrosis, inflammation, hypertrophy and fibrosis following MI, accompanied by exaggerated HSPC activity and impaired macrophage phenotype. These findings suggest that endogenous ANX-A1 regulates mobilisation and differentiation of HSPCs. Limiting excessive monocyte/neutrophil production may limit LV damage in vivo. Our findings support further development of novel ANX-A1-based therapies to improve cardiac outcomes after MI.


  • Qin, Cheng Xue
  • Finlayson, Siobhan B
  • Al-Sharea, Annas
  • Tate, Mitchel
  • De Blasio, Miles J
  • Deo, Minh
  • Rosli, Sarah
  • Prakoso, Darnel
  • Thomas, Colleen J
  • Kiriazis, Helen
  • Gould, Eleanor
  • Yang, Yuan H
  • Morand, Eric F
  • Perretti, Mauro
  • Murphy, Andrew J
  • Du, Xiao-Jun
  • Gao, Xiao-Ming
  • Ritchie, Rebecca H

publication date

  • 2017