title: PEP-1-CAT-transduced mesenchymal stem cells acquire an enhanced viability and promote ischemia-induced angiogenesis.
abstract: OBJECTIVE
  Poor survival of mesenchymal stem cells (MSC) compromised the efficacy of stem cell therapy for ischemic diseases. The aim of this study is to investigate the role of PEP-1-CAT transduction in MSC survival and its effect on ischemia-induced angiogenesis.
  
  
  METHODS
  MSC apoptosis was evaluated by DAPI staining and quantified by Annexin V and PI double staining and Flow Cytometry. Malondialdehyde (MDA) content, lactate dehydrogenase (LDH) release, and Superoxide Dismutase (SOD) activities were simultaneously measured. MSC mitochondrial membrane potential was analyzed with JC-1 staining. MSC survival in rat muscles with gender-mismatched transplantation of the MSC after lower limb ischemia was assessed by detecting SRY expression. MSC apoptosis in ischemic area was determined by TUNEL assay. The effect of PEP-1-CAT-transduced MSC on angiogenesis in vivo was determined in the lower limb ischemia model.
  
  
  RESULTS
  PEP-1-CAT transduction decreased MSC apoptosis rate while down-regulating MDA content and blocking LDH release as compared to the treatment with H(2)O(2) or CAT. However, SOD activity was up-regulated in PEP-1-CAT-transduced cells. Consistent with its effect on MSC apoptosis, PEP-1-CAT restored H(2)O(2)-attenuated mitochondrial membrane potential. Mechanistically, PEP-1-CAT blocked H(2)O(2)-induced down-regulation of PI3K/Akt activity, an essential signaling pathway regulating MSC apoptosis. In vivo, the viability of MSC implanted into ischemic area in lower limb ischemia rat model was increased by four-fold when transduced with PEP-1-CAT. Importantly, PEP-1-CAT-transduced MSC significantly enhanced ischemia-induced angiogenesis by up-regulating VEGF expression.
  
  
  CONCLUSIONS
  PEP-1-CAT-transduction was able to increase MSC viability by regulating PI3K/Akt activity, which stimulated ischemia-induced angiogenesis.
authors.affiliation: Institute of Clinical Medicine and Department of Cardiology, Renmin Hospital, Hubei University of Medicine, Shiyan, Hubei, People's Republic of China.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhang
authors.forename: Xiao-Wei
authors.initials: XW
authors.lastname: Dong
authors.forename: Jia-Ning
authors.initials: JN
authors.lastname: Wang
authors.forename: Jun-Ming
authors.initials: JM
authors.lastname: Tang
authors.forename: Jian-Ye
authors.initials: JY
authors.lastname: Yang
authors.forename: Ling-Yun
authors.initials: LY
authors.lastname: Guo
authors.forename: Fei
authors.initials: F
authors.lastname: Zheng
authors.forename: Xia
authors.initials: X
authors.lastname: Kong
authors.forename: Yong-Zhang
authors.initials: YZ
authors.lastname: Huang
authors.forename: Shi-You
authors.initials: SY
authors.lastname: Chen
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D002374:Catalase / Q000378:metabolism; D002470:Cell Survival / Q000187:drug effects; D006861:Hydrogen Peroxide / Q000494:pharmacology; D007511:Ischemia / Q000473:pathology / Q000628:therapy*; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D035002:Lower Extremity / Q000098:blood supply / Q000473:pathology / Q000503:physiopathology; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D045164:Mesenchymal Stem Cell Transplantation; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000378:metabolism*; D051379:Mice; D018919:Neovascularization, Physiologic; D010641:Phenotype; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects; D013482:Superoxide Dismutase / Q000378:metabolism; D014161:Transduction, Genetic; D015854:Up-Regulation / Q000187:drug effects; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
chemical_list: D011993:Recombinant Fusion Proteins; D042461:Vascular Endothelial Growth Factor A; D008315:Malondialdehyde; D006861:Hydrogen Peroxide; D007770:L-Lactate Dehydrogenase; D002374:Catalase; C558128:PEP-1-catalase fusion protein; D013482:Superoxide Dismutase; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt