IGF-1 Regulates the extracellular level of active MMP-2 and promotes Müller glial cell motility

 

Autores
Lorenc, Valeria Erika; Jaldín Fincati, Javier Roberto; Luna Pinto, Jose Domingo; Chiabrando, Gustavo Alberto; Sanchez, Maria Cecilia
Tipo de recurso
artículo
Estado
Versión publicada
Año de publicación
2015
País
Argentina
Institución
Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio
CONICET Digital (CONICET)
Descripción
In ischemic proliferative retinopathies, Müller glial cells (MGCs) acquire migratory abilities. However, the mechanisms that regulate this migration remain poorly understood. In addition, proliferative disorders associated with enhanced activities of matrix metalloproteinases (MMPs) also involve insulin-like growth factor (IGF)-1 participation. Therefore, the main interest of this work was to investigate the IGF-1 effect on the extracellular proteolytic activity in MGCs.Methods: Cell culture supernatants and cell lysates of the human MGC line MIO-M1 stimulated with IGF-1 were analyzed for MMP-2 by zymographic and Western blot analysis. The MGCs´ motility was evaluated by scratch wound assay. The MMP-2, β1-integrin, and focal adhesions were detected by confocal microscopy. The localization of active MMPs and actin cytoskeleton were evaluated by in situ zymography.Results: The IGF-1 induced the activation of canonical signaling pathways through the IGF-1R phosphorylation. Culture supernatants showed a relative decrease in the active form of MMP-2, correlating with an increased accumulation of MMP-2 protein in the MGCs´ lysate. The IGF-1 effect on MMP-2 was abolished by an IGF-1R blocking antibody, αIR3, as well as by the PI3-kinase inhibitor, LY294002. The IGF-1 increased the migratory capacity of MGCs, which was blocked by the GM6001 MMP inhibitor, LY294002 and αIR3. Finally, IGF-1 induced the intracellular distribution of MMP-2 toward cellular protrusions and the partial colocalization with β1-integrin and phospo-focal adhesion kinase signals. Gelatinase activity was concentrated along F-actin filaments.Conclusions: Taken together, these data indicate that IGF-1, through its receptor activation, regulates MGCs´ motility by a mechanism that involves the MMP-2 and PI3K signaling pathway.
Idioma
inglés
OAI Identifier
oai:ri.conicet.gov.ar:11336/46437
Enlace del recurso
http://hdl.handle.net/11336/46437
Nivel de acceso
Acceso abierto
Materia
RETINA
GLIA
PROTEASES
MIGRATION
Inmunología
Medicina Básica
CIENCIAS MÉDICAS Y DE LA SALUD