Transfusion of CXCR4-primed endothelial progenitor cells reduces cerebral ischemic damage and promotes repair in db/db diabetic mice

PLoS One. 2012;7(11):e50105. doi: 10.1371/journal.pone.0050105. Epub 2012 Nov 21.

Abstract

This study investigated the role of stromal cell-derived factor-1α (SDF-1α)/CXC chemokine receptor 4 (CXCR4) axis in brain and endothelial progenitor cells (EPCs), and explored the efficacy of CXCR4 primed EPCs in treating ischemic stroke in diabetes. The db/db diabetic and db/+ mice were used in this study. Levels of plasma SDF-1α and circulating CD34+CXCR4+ cells were measured. Brain SDF-1α and CXCR4 expression were quantified at basal and after middle cerebral artery occlusion (MCAO). In in vitro study, EPCs were transfected with adenovirus carrying null (Ad-null) or CXCR4 (Ad-CXCR4) followed with high glucose (HG) treatment for 4 days. For pathway block experiments, cells were pre-incubated with PI3K inhibitor or nitric oxide synthase (NOS) inhibitor for two hours. The CXCR4 expression, function and apoptosis of EPCs were determined. The p-Akt/Akt and p-eNOS/eNOS expression in EPCs were also measured. In in vivo study, EPCs transfected with Ad-null or Ad-CXCR4 were infused into mice via tail vein. On day 2 and 7, the cerebral blood flow, neurologic deficit score, infarct volume, cerebral microvascular density, angiogenesis and neurogenesis were determined. We found: 1) The levels of plasma SDF-1α and circulating CD34+CXCR4+ cells were decreased in db/db mice; 2) The basal level of SDF-1α and MCAO-induced up-regulation of SDF-1α/CXCR4 axis were reduced in the brain of db/db mice; 3) Ad-CXCR4 transfection increased CXCR4 expression in EPCs and enhanced EPC colonic forming capacity; 4) Ad-CXCR4 transfection prevented EPCs from HG-induced dysfunction (migration and tube formation) and apoptosis via activation of PI3K/Akt/eNOS signal pathway; 4) Ad-CXCR4 transfection enhanced the efficacy of EPC infusion in attenuating infarct volume and promoting angiogenesis and neurogenesis. Our data suggest that Ad-CXCR4 primed EPCs have better therapeutic effects for ischemia stroke in diabetes than unmodified EPCs do.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenoviridae / genetics
  • Animals
  • Brain / blood supply*
  • Brain / metabolism
  • Brain / pathology
  • Brain Ischemia / genetics
  • Brain Ischemia / metabolism
  • Brain Ischemia / pathology
  • Brain Ischemia / therapy*
  • Chemokine CXCL12 / genetics*
  • Chemokine CXCL12 / metabolism
  • Diabetes Mellitus, Type 2 / genetics
  • Diabetes Mellitus, Type 2 / metabolism
  • Diabetes Mellitus, Type 2 / pathology
  • Diabetes Mellitus, Type 2 / therapy*
  • Disease Models, Animal
  • Endothelial Cells / cytology
  • Endothelial Cells / metabolism*
  • Endothelial Cells / transplantation
  • Enzyme Inhibitors / pharmacology
  • Gene Expression Regulation
  • Genetic Vectors
  • Male
  • Mice
  • Neovascularization, Physiologic
  • Neurogenesis / physiology
  • Phosphatidylinositol 3-Kinases / genetics
  • Phosphatidylinositol 3-Kinases / metabolism
  • Phosphoinositide-3 Kinase Inhibitors
  • Proto-Oncogene Proteins c-akt / antagonists & inhibitors
  • Proto-Oncogene Proteins c-akt / genetics
  • Proto-Oncogene Proteins c-akt / metabolism
  • Receptors, CXCR4 / genetics*
  • Receptors, CXCR4 / metabolism
  • Signal Transduction
  • Stem Cell Transplantation
  • Stem Cells / cytology
  • Stem Cells / metabolism*
  • Transfection

Substances

  • CXCR4 protein, mouse
  • Chemokine CXCL12
  • Enzyme Inhibitors
  • Phosphoinositide-3 Kinase Inhibitors
  • Receptors, CXCR4
  • Proto-Oncogene Proteins c-akt