title: Mesenchymal stem cells enhance the viability and proliferation of human fetal intestinal epithelial cells following hypoxic injury via paracrine mechanisms.
abstract: BACKGROUND
  Mesenchymal stem cells (MSCs) may be used to treat injured tissues. The ability of MSCs to treat injured fetal intestinal epithelial cells (FIEs), similar to those in infants with necrotizing enterocolitis, has not been elucidated. We hypothesized that MSCs would enhance FIE viability and proliferation after hypoxic injury via paracrine mechanisms.
  
  
  METHODS
  LLC-PK1 cells (differentiated control [DC]) and human MSCs were exposed to 1 hour of hypoxia. Cells were reoxygenated for 24 hours and cell-free conditioned media were collected. Human FIEs were exposed to 1 hour of hypoxia and plated for experiments. FIEs were reoxygenated in nonconditioned media, DC-conditioned media, or MSC-conditioned media. Supernatants were analyzed for interleukin-6 (IL-6), hepatocyte growth factor (HGF), fibroblast growth factor (FGF), and vascular endothelial growth factor (VEGF) via enzyme-linked immunosorbent assay. Cell viability was assessed by trypan blue exclusion and cell counting. Proliferation was determined via 5-bromo-2'-deoxyuridine (BrdU). Expression of caspases-3 and -8 was determined via Western blot.
  
  
  RESULTS
  FIEs reoxygenated in MSC-conditioned media demonstrated enhanced viability and increased proliferation after hypoxic injury. Enhanced FIE viability and proliferation were associated with increased IL-6, HGF, and VEGF, as well as decreased expression of caspase-3.
  
  
  CONCLUSIONS
  MSCs may increase the viability and proliferative capacity of FIEs after hypoxic injury via the paracrine release of IL-6, HGF, and VEGF, as well as downregulation of apoptotic signaling.
authors.affiliation: Department of Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
authors.forename: Brent R
authors.initials: BR
authors.lastname: Weil
authors.forename: Troy A
authors.initials: TA
authors.lastname: Markel
authors.forename: Jeremy L
authors.initials: JL
authors.lastname: Herrmann
authors.forename: Aaron M
authors.initials: AM
authors.lastname: Abarbanell
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Meldrum
mesh_terms: D000818:Animals; D020169:Caspases / Q000378:metabolism; D015687:Cell Hypoxia; D049109:Cell Proliferation; D002470:Cell Survival; D002478:Cells, Cultured; D017077:Culture Media, Conditioned / Q000737:chemistry; D005333:Fetus / Q000166:cytology; D017228:Hepatocyte Growth Factor / Q000378:metabolism; D006801:Humans; D015850:Interleukin-6 / Q000378:metabolism; D007413:Intestinal Mucosa / Q000166:cytology* / Q000378:metabolism; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D018374:LLC-PK1 Cells; D059630:Mesenchymal Stem Cells / Q000378:metabolism / Q000502:physiology*; D019899:Paracrine Communication; D013552:Swine; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
chemical_list: D017077:Culture Media, Conditioned; D015850:Interleukin-6; D042461:Vascular Endothelial Growth Factor A; D017228:Hepatocyte Growth Factor; D007770:L-Lactate Dehydrogenase; D020169:Caspases