title: Mesenchymal stem cells protect podocytes from apoptosis induced by high glucose via secretion of epithelial growth factor.
abstract: BACKGROUND
  The apoptosis and subsequent injury of podocytes plays a pathogenic role in diabetic nephropathy (DN). Mesenchymal stem cells (MSCs) are promising therapeutic cells for preventing apoptosis and reducing cellular injury. Our previous study found that MSCs could protect kidneys from diabetes-induced injury without obvious engraftment. So we evaluated the effects of human adipose-derived MSCs (hAd-MSCs) on podocytic apoptosis and injury induced by high glucose (HG) and the underlying mechanisms.
  
  
  METHODS
  We used flow cytometry, Western blot and confocal fluorescence microscopy to study podocytic apoptosis and injury induced by HG at 24 hours, 48 hours, and 72 hours in the presence or absence of MSC-conditioned medium (CM). An antibody-based cytokine array was used to identify the mediating factor, which was verified by adding the neutralizing antibody (NtAb) to block its function or adding the recombinant cytokine to the medium to induce its function.
  
  
  RESULTS
  hAd-MSC-CM reduced podocytic apoptosis in a dose-dependent manner, decreased the expression of podocytic cleaved caspase-3, and prevented the reduced expression and maintained the normal arrangement of podocytic synaptopodin and nephrin. However, human embryonic lung cell (Wi38)-CM failed to ameliorate podocytic apoptosis or injury. Twelve cytokines with concentration ratios (MSC-CM/Wi38-CM) >10-fold were identified. Epithelial growth factor (EGF) was singled out for its known ability to prevent apoptosis. Recombinant human EGF (rhEGF) prevented podocytic apoptosis and injury similarly to hAd-MSC-CM but, upon blockade of EGF, the beneficial effect of hAd-MSC-CM decreased dramatically.
  
  
  CONCLUSIONS
  hAd-MSCs prevent podocytic apoptosis and injury induced by HG, mainly through secreting soluble EG.
authors.forename: Diangeng
authors.initials: D
authors.lastname: Li
authors.forename: Nan
authors.initials: N
authors.lastname: Wang
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.forename: Zhu
authors.initials: Z
authors.lastname: Hanyu
authors.forename: Bai
authors.initials: B
authors.lastname: Xueyuan
authors.forename: Bo
authors.initials: B
authors.lastname: Fu
authors.forename: Cui
authors.initials: C
authors.lastname: Shaoyuan
authors.forename: Weiguang
authors.initials: W
authors.lastname: Zhang
authors.forename: Sun
authors.initials: S
authors.lastname: Xuefeng
authors.forename: Rongshan
authors.initials: R
authors.lastname: Li
authors.forename: Xiangmei
authors.initials: X
authors.lastname: Chen
mesh_terms: D000273:Adipose Tissue / Q000166:cytology; D000818:Animals; D057134:Antibodies, Neutralizing / Q000276:immunology; D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3 / Q000378:metabolism; D002478:Cells, Cultured; D017077:Culture Media, Conditioned / Q000494:pharmacology; D016207:Cytokines / Q000032:analysis; D004815:Epidermal Growth Factor / Q000235:genetics / Q000378:metabolism*; D005947:Glucose / Q000494:pharmacology*; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000378:metabolism*; D051379:Mice; D050199:Podocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics / Q000494:pharmacology; D016708:Synaptophysin / Q000378:metabolism; D013997:Time Factors
chemical_list: D057134:Antibodies, Neutralizing; D017077:Culture Media, Conditioned; D016207:Cytokines; D008565:Membrane Proteins; D011994:Recombinant Proteins; D016708:Synaptophysin; C113267:nephrin; D004815:Epidermal Growth Factor; D053148:Caspase 3; D005947:Glucose