title: Protection of Brain Injury by Amniotic Mesenchymal Stromal Cell-Secreted Metabolites.
abstract: OBJECTIVE
  To define the features of human amniotic mesenchymal stromal cell secretome and its protective properties in experimental models of acute brain injury.
  
  
  METHODS
  Prospective experimental study.
  
  
  METHODS
  Laboratory research.
  
  
  METHODS
  C57Bl/6 mice.
  
  
  METHODS
  Mice subjected to sham or traumatic brain injury by controlled cortical impact received human amniotic mesenchymal stromal cells or phosphate-buffered saline infused intracerebroventricularly or intravenously 24 hours after injury. Organotypic cortical brain slices exposed to ischemic injury by oxygen-glucose deprivation were treated with human amniotic mesenchymal stromal cells or with their secretome (conditioned medium) in a transwell system.
  
  
  RESULTS
  Traumatic brain injured mice receiving human amniotic mesenchymal stromal cells intravenously or intracerebroventricularly showed early and lasting functional and anatomical brain protection. cortical slices injured by oxigen-glucose deprivation and treated with human amniotic mesenchymal stromal cells or conditioned medium showed comparable protective effects (neuronal rescue, promotion of M2 microglia polarization, induction of trophic factors) indicating that the exposure of human amniotic mesenchymal stromal cells to the injured tissue is not necessary for the release of bioactive factors. Using sequential size-exclusion and gel-filtration chromatography, we identified a conditioned medium subfraction, which specifically displays these highly protective properties and we found that this fraction was rich in bioactive molecules with molecular weight smaller than 700 Da. Quantitative RNA analysis and mass spectrometry-based peptidomics showed that the active factors are not proteins or RNAs. The metabolomic profiling of six metabolic classes identified a list of molecules whose abundance was selectively elevated in the active conditioned medium fraction.
  
  
  CONCLUSIONS
  Human amniotic mesenchymal stromal cell-secreted factors protect the brain after acute injury. Importantly, a fraction rich in metabolites, and containing neither proteic nor ribonucleic molecules was protective. This study indicates the profiling of protective factors that could be useful in cell-free therapeutic approaches for acute brain injury.
authors.affiliation: 1Department of Neuroscience, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy. 2Department of Environmental Health Sciences, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy. 3Centro di Ricerca E. Menni, Fondazione Poliambulanza-Istituto Ospedaliero, Brescia, Italy. 4Department of Cerebrovascular Diseases, Fondazione IRCCS-Istituto Neurologico Carlo Besta, Milan, Italy. 5Department of Oncology, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy. 6Department of Biochemistry, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Pischiutta
authors.forename: Laura
authors.initials: L
authors.lastname: Brunelli
authors.forename: Pietro
authors.initials: P
authors.lastname: Romele
authors.forename: Antonietta
authors.initials: A
authors.lastname: Silini
authors.forename: Eliana
authors.initials: E
authors.lastname: Sammali
authors.forename: Lara
authors.initials: L
authors.lastname: Paracchini
authors.forename: Sergio
authors.initials: S
authors.lastname: Marchini
authors.forename: Laura
authors.initials: L
authors.lastname: Talamini
authors.forename: Paolo
authors.initials: P
authors.lastname: Bigini
authors.forename: Giorgio B
authors.initials: GB
authors.lastname: Boncoraglio
authors.forename: Roberta
authors.initials: R
authors.lastname: Pastorelli
authors.forename: Maria-Grazia
authors.initials: MG
authors.lastname: De Simoni
authors.forename: Ornella
authors.initials: O
authors.lastname: Parolini
authors.forename: Elisa R
authors.initials: ER
authors.lastname: Zanier
mesh_terms: D000650:Amnion / Q000166:cytology*; D000818:Animals; D001522:Behavior, Animal; D001930:Brain Injuries / Q000517:prevention & control*; D019208:Brain-Derived Neurotrophic Factor / Q000378:metabolism; D039481:CD11b Antigen / Q000378:metabolism; D017077:Culture Media, Conditioned; D004195:Disease Models, Animal; D015536:Down-Regulation; D005904:Glial Fibrillary Acidic Protein / Q000235:genetics / Q000378:metabolism; D006801:Humans; D045164:Mesenchymal Stem Cell Transplantation; D059630:Mesenchymal Stem Cells / Q000378:metabolism / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000378:metabolism; D011446:Prospective Studies; D012333:RNA, Messenger / Q000378:metabolism; D015854:Up-Regulation; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
chemical_list: D019208:Brain-Derived Neurotrophic Factor; D039481:CD11b Antigen; D017077:Culture Media, Conditioned; D005904:Glial Fibrillary Acidic Protein; D008869:Microtubule-Associated Proteins; C079240:Mtap2 protein, mouse; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D012333:RNA, Messenger; D042461:Vascular Endothelial Growth Factor A; C528900:glial fibrillary astrocytic protein, mouse