Oncostatin M is a novel glucocorticoid-dependent neuroinflammatory factor that enhances oligodendrocyte precursor cell activity in demyelinated sites

Autor(es)

Glezer, Isaias ; Rivest, Serge

• Tipo de documento: Artigo Científico
• Fonte: BRAIN BEHAVIOR AND IMMUNITY; v. 24, n. 5, p. 10-pg., 2010-07-01.

Resumo

The innate immune reaction to tissue injury is a natural process, which can have detrimental effects in the absence of negative feedbacks by glucocorticoids (GCs). Although acute lipopolysaccharide (LPS) challenge is relatively harmless to the brain parenchyma of adult animals, the endotoxin is highly neurotoxic in animals that are treated with the GC receptor antagonist RU486. This study investigated the role of cytokines of the gp130-related family in these effects, because they are essential components of the inflammatory process that provide survival signals to neurons. Intracerebral LPS injection stimulated expression of several members of this family of cytokines, but oncostatin M (Osm) was the unique ligand to be completely inhibited by the RU486 treatment. OSM receptor (Osmr) is expressed mainly in astrocytes and endothelial cells following LPS administration and GCs are directly responsible for its transcriptional activation in the presence of the endotoxin. In a mouse model of demyelination, exogenous OSM significantly modulated the expression of genes involved in the mobilization of oligodendrocyte precursor cells (OPCs), differentiation of oligodendrocyte, and production of myelin. In conclusion, the activation of OSM signaling is a mechanism activated by TLR4 in the presence of negative feedback by GCs on the innate immune system of the brain. OSM absence is associated with detrimental effects of LPS, whereas exogenous OSM favors repair response to demyelinated regions. (C) 2010 Elsevier Inc. All rights reserved. (AU)

• Processo FAPESP: 07/53732-8 - Estudo da regeneração celular pós-lesão no sistema nervoso e avaliação da contribuição e dos aspectos funcionais de genes ligados à resposta imune inata
• Beneficiário: Isaias Glezer
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores
• Processo FAPESP: 08/55645-8 - Alteracao e regeneracao da sinalizacao olfatoria atraves da manipulacao da expressao genica e da inflamacao no epitelio olfatorio
• Beneficiário: Isaias Glezer
• Modalidade de apoio: Bolsas no Brasil - Jovens Pesquisadores