Ischaemia/reperfusion induced cardiac stem cell homing to the injured myocardium by stimulating stem cell factor expression via NF-kappaB pathway

Int J Exp Pathol. 2009 Jun;90(3):355-64. doi: 10.1111/j.1365-2613.2009.00659.x.

Abstract

Ischaemia/reperfusion (I/R) is a major cause of heart failure. Recently cardiac stem cells (CSCs) were proposed as the most appropriate cell type for heart disease therapy. However, it is still unclear whether I/R can stimulate the CSCs homing to the injured myocardium. Male Sprague-Dawley rats were subjected to a 30-min ischaemia followed by reperfusion of different intervals. RT-PCR, western blotting and immunohistochemistry were performed to detect stem cell factor (SCF) expression at mRNA and protein levels respectively. Activation of nuclear factor-kappaB (NF-kappaB) was determined by electrophoretic mobility shift assay. To assess the homing of CSCs in vivo, BrdU-labelled CSCs were injected into AV-groove before induction of ischaemia and examined by immunofluorescent staining in the injured myocardium after I/R. From day 3 to day 6 after reperfusion, the accumulation of CSCs was significantly elevated in the injured area, which was matched with the increased SCF expression during I/R. Pretreatment of rats with NF-kappaB inhibitor, N-acetyl-L-cysteine (NAC) not only suppressed NF-kappaB activation induced by I/R but also attenuated SCF expression. Further analysis revealed that I/R induced phosphorylation of IkappaBalpha after 15 min of reperfusion, and the raised phosphor-IkappaBalpha returned to the basal level at 2 h of reperfusion. In simulated I/R(SI/R) in vitro, it enhanced NF-kappaB activation and SCF expression in cultured neonatal rat cardiomyocytes, which was markedly inhibited by NF-kappaB decoy oligodeoxynucleotide or NAC. Taken together, our results demonstrated that I/R induced CSCs homing to the injured myocardium by stimulating myocardial SCF expression via activation of NF-kappaB.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Movement / physiology
  • Cells, Cultured
  • DNA-Binding Proteins / metabolism
  • I-kappa B Proteins / metabolism
  • Male
  • Myocytes, Cardiac / metabolism
  • NF-KappaB Inhibitor alpha
  • NF-kappa B / physiology*
  • Phosphorylation
  • Rats
  • Rats, Sprague-Dawley
  • Reperfusion Injury / metabolism
  • Reperfusion Injury / pathology*
  • Reperfusion Injury / physiopathology
  • Signal Transduction / physiology
  • Stem Cell Factor / metabolism*
  • Stem Cell Factor / physiology
  • Stem Cells / physiology*
  • Ventricular Function, Left

Substances

  • DNA-Binding Proteins
  • I-kappa B Proteins
  • NF-kappa B
  • Nfkbia protein, rat
  • Stem Cell Factor
  • NF-KappaB Inhibitor alpha