Mesenchymal stem cell-conditioned medium triggers neuroinflammation and reactive species generation in organotypic cultures of rat hippocampus.
Cell therapy using bone marrow-derived mesenchymal stem cells (MSCs) seems to be a new alternative for the treatment of neurodegenerative diseases. Despite several promising results with their use, possible side effects are still unknown. In a previous work, we have shown that MSC-conditioned medium is toxic to hippocampal slice cultures and aggravates cell death induced by oxygen and glucose deprivation. In this work, we investigated whether the inflammatory response and/or reactive species formation could be involved in that toxicity. Rat organotypic hippocampal cultures were exposed for 24 h to conditioned medium from MSCs isolated from rat bone marrow. A marked glial activation was observed after exposure of cultures to MSC-conditioned medium, as evidenced by glial fibrillary acid protein (GFAP) and isolectin B(4) increase. Tumor necrosis factor-α and interleukin-6 levels were increased in the culture medium, and 2,7-dihydrodichlorofluorescein diacetate oxidation (indicating reactive species generation) and inducible nitric oxide synthase (iNOS) immunocontent were also higher after exposure of cultures to MSC-conditioned medium. Antioxidants (ascorbic acid and TROLOX(®)), N(ω)-nitro-l-arginine methyl ester hydrochloride, and anti-inflammatory drugs (indomethacin and dexamethasone) reduced cell death in hippocampal organotypic cultures after their exposure to MSC-conditioned medium. The results obtained here suggest that MSC-secreted factors trigger reactive species generation and neuroinflammation in organotypic cultures of hippocampus, introducing a note of caution in the use of these cells for neurological application.
Programa de Pós-Graduação em Ciências Biológicas, Bioquímica, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, UFRGS, Porto Alegre, RS, Brazil. anapaulahorn@yahoo.com.br
Ana Paula
AP
Horn
Andressa
A
Bernardi
Rudimar
R
Luiz Frozza
Patrícia Bencke
PB
Grudzinski
Juliana Bender
JB
Hoppe
Luiz Fernando
LF
de Souza
Pedro
P
Chagastelles
Angela Terezinha
AT
de Souza Wyse
Elena Aida
EA
Bernard
Ana Maria Oliveira
AM
Battastini
Maria Martha
MM
Campos
Guido
G
Lenz
Nance Beyer
NB
Nardi
Christianne
C
Salbego
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology; D015153:Blotting, Western; D001854:Bone Marrow Cells / Q000378:metabolism; D016923:Cell Death; D002478:Cells, Cultured; D017077:Culture Media, Conditioned / Q000494:pharmacology*; D006023:Glycoproteins / Q000378:metabolism; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects*; D066298:In Vitro Techniques; D007378:Interleukins / Q000032:analysis; D037102:Lectins / Q000378:metabolism; D008297:Male; D059630:Mesenchymal Stem Cells / Q000378:metabolism*; D020078:Neurogenic Inflammation / Q000378:metabolism*; D009457:Neuroglia / Q000187:drug effects; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D018384:Oxidative Stress; D051381:Rats; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis; D053675:Versicans
D000893:Anti-Inflammatory Agents; D017077:Culture Media, Conditioned; D006023:Glycoproteins; D007378:Interleukins; D037102:Lectins; D017382:Reactive Oxygen Species; D014409:Tumor Necrosis Factor-alpha; C508324:Vcan protein, rat; D053675:Versicans; D052247:Nitric Oxide Synthase Type II