title: Inflammatory cytokine induced regulation of superoxide dismutase 3 expression by human mesenchymal stem cells.
abstract: Increasing evidence suggests that bone marrow derived-mesenchymal stem cells (MSCs) have neuroprotective properties and a major mechanism of action is through their capacity to secrete a diverse range of potentially neurotrophic or anti-oxidant factors. The recent discovery that MSCs secrete superoxide dismutase 3 (SOD3) may help explain studies in which MSCs have a direct anti-oxidant activity that is conducive to neuroprotection in both in vivo and in vitro. SOD3 attenuates tissue damage and reduces inflammation and may confer neuroprotective effects against nitric oxide-mediated stress to cerebellar neurons; but, its role in relation to central nervous system inflammation and neurodegeneration has not been extensively investigated. Here we have performed a series of experiments showing that SOD3 secretion by human bone marrow-derived MSCs is regulated synergistically by the inflammatory cytokines TNF-alpha and IFN-gamma, rather than through direct exposure to reactive oxygen species. Furthermore, we have shown SOD3 secretion by MSCs is increased by activated microglial cells. We have also shown that MSCs and recombinant SOD are able to increase both neuronal and axonal survival in vitro against nitric oxide or microglial induced damage, with an increased MSC-induced neuroprotective effect evident in the presence of inflammatory cytokines TNF-alpha and IFN-gamma. We have shown MSCs are able to convey these neuroprotective effects through secretion of soluble factors alone and furthermore demonstrated that SOD3 secretion by MSCs is, at least, partially responsible for this phenomenon. SOD3 secretion by MSCs maybe of relevance to treatment strategies for inflammatory disease of the central nervous system.
authors.affiliation: Multiple Sclerosis and Stem Cell Group, Institute of Clinical Neurosciences, Clinical Sciences North Bristol, University of Bristol, Bristol, UK. kevin.kemp@bristol.ac.uk
authors.forename: Kevin
authors.initials: K
authors.lastname: Kemp
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Gray
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Mallam
authors.forename: Neil
authors.initials: N
authors.lastname: Scolding
authors.forename: Alastair
authors.initials: A
authors.lastname: Wilkins
mesh_terms: D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D016207:Cytokines / Q000494:pharmacology*; D004357:Drug Synergism; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D015151:Immunoblotting; D007150:Immunohistochemistry; D007371:Interferon-gamma / Q000494:pharmacology; D059630:Mesenchymal Stem Cells / Q000187:drug effects* / Q000378:metabolism*; D009474:Neurons / Q000166:cytology / Q000187:drug effects; D009569:Nitric Oxide / Q000494:pharmacology; D016133:Polymerase Chain Reaction; D051381:Rats; D013482:Superoxide Dismutase / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
chemical_list: D016207:Cytokines; D014409:Tumor Necrosis Factor-alpha; D009569:Nitric Oxide; D007371:Interferon-gamma; C441642:SOD3 protein, human; D013482:Superoxide Dismutase