TGF-b pro-oligodendrogenic effects on adult SVZ progenitor cultures and its interaction with

ANA ADAMO; DEBORA VANESA RODRIGUEZ; LAURA IVONNE GOMEZ PINTO; PATRICIA MATHIEU

GLIA

WILEY-LISS, DIV JOHN WILEY & SONS INC

Lugar: New York; Año: 2018

0894-1491

Adult neural progenitor cells (NPCs) are capable of differentiating into neurons, astrocytes and oligodendrocytes (OLs) throughout life. Notch and transforming growth factor beta 1 (TGF-β) signaling pathways play critical roles in controlling these cell fate decisions. TGF-β has been previously shown to exert proneurogenic effects on hippocampal and subventricular zone (SVZ) NPCs in vitro and to interact with Notch in different cellular types. Therefore, the aim of our work was to study the effect of TGF-β on adult rat brain SVZ NPC glial commitment and its interaction with Notch signaling. Initial cell characterization revealed a large proportion of Olig2+, Nestin+ and GFAP+ cells, a low percentage of PDGFRα+ or NG2+ cells, and less than 1% Tuj1+ cells. Immunocytochemical analyses showed a significant increase in the percentage of PDGFRα+, NG2+ and GFAP+ cells upon four-day TGF-β treatment, which demonstrates the pro-gliogenic effect of this growth factor on adult brain SVZ NPCs. Real-time polymerase chain reaction (PCR) analyses showed that TGF-β induced the expression of Notch ligand Jagged1 and downstream gene Hes1. Notch signaling inhibition in cultures treated with TGF-β produced a decrease in the proportion of PDGFRα+ cells, while TGF-β receptor II (TβRII) inhibition also rendered a decrease in the proportion of PDGFRα+ cells, concomitantly with a decrease in Jagged1 levels. These findings demonstrate the participation of Notch signaling in TGF-β effects and illustrate the impact of TGF-β on glial cell fate decisions of adult brain SVZ NPCs, as well as on oligodendroglial progenitor cell (OPC) proliferation and maturation.