title: Immobilized kidney 28-kDa endostatin-related (KES28kDa) fragment promotes endothelial cell survival.
abstract: OBJECTIVE
  Renal ischemia-hypoxia is a leading cause of acute kidney injury (AKI). Ischemia causes extracellular matrix breakdown of the tubular basement membrane. Endostatin (ES) is the C-terminal fragment of collagen XVIII generated by proteolytic cleavage. Recent studies have demonstrated that ES expression is upregulated in ischemic kidneys. The present study aimed to characterize ES from ischemic kidneys.
  
  
  METHODS
  Ischemic renal failure was induced via 45 min of occlusion of the left renal artery and vein. After the ischemic period, blood was collected. Kidneys were harvested and used for immunohistochemical testing and protein extraction. Three-step purification was used. Soluble and immobilized purified ES were tested in cell viability and adhesion assays. results: The soluble KES28kDa inhibited endothelial cell proliferation: 25 versus 12.5 microg (p < 0.05); 12.5 versus 3.15 microg (p < 0.05). Immobilization of KES28kDa supports endothelial cell survival over the control (p = 0.021). Human umbilical vein endothelial cells plated on immobilized KES28kDa showed an increase in membrane ruffles and stress fibers.
  
  
  CONCLUSIONS
  These data demonstrate the local synthesis of a 28-kDa ES-related fragment following AKI and suggest its role in endothelium survival.
authors.affiliation: Center of Biotechnology, Energy and Nuclear Research Institute - IPEN, Universidade Federal de São Paulo, Brazil. mhmarumo@terra.com.br
authors.forename: Maria Helena
authors.initials: MH
authors.lastname: Bellini
authors.forename: Thiago França
authors.initials: TF
authors.lastname: Malpighi
authors.forename: Fernanda Bernardes
authors.initials: FB
authors.lastname: Calvo
authors.forename: Adriana Regina
authors.initials: AR
authors.lastname: Miranda
authors.forename: Patrick Jack
authors.initials: PJ
authors.lastname: Spencer
authors.forename: Milena Cristina
authors.initials: MC
authors.lastname: Cichy
authors.forename: Simone Michaela
authors.initials: SM
authors.lastname: Simons
authors.forename: Ana Marisa
authors.initials: AM
authors.lastname: Chudzinski Tavassi
authors.forename: Marinilce
authors.initials: M
authors.lastname: Fagundes dos Santos
authors.forename: Consuelo
authors.initials: C
authors.lastname: Junqueira Rodrigues
authors.forename: Nestor
authors.initials: N
authors.lastname: Schor
mesh_terms: D058186:Acute Kidney Injury / Q000378:metabolism* / Q000473:pathology*; D000818:Animals; D002448:Cell Adhesion / Q000502:physiology; D002455:Cell Division / Q000502:physiology; D002470:Cell Survival / Q000502:physiology; D004195:Disease Models, Animal; D043169:Endostatins / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*; D042783:Endothelial Cells / Q000166:cytology / Q000378:metabolism; D006801:Humans; D055767:Immobilized Proteins; D007150:Immunohistochemistry; D007511:Ischemia / Q000378:metabolism*; D007668:Kidney / Q000378:metabolism; D007677:Kidney Function Tests; D051379:Mice; D008810:Mice, Inbred C57BL; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D012995:Solubility; D022502:Stress Fibers / Q000378:metabolism; D014471:Umbilical Veins / Q000166:cytology
chemical_list: D043169:Endostatins; D055767:Immobilized Proteins; D010446:Peptide Fragments; D012333:RNA, Messenger