Short and long TNF‐alpha exposure recapitulates canonical astrogliosis events in human‐induced pluripotent stem cells‐derived astrocytes. Issue 7 (31st January 2020)

• Record Type: Journal Article
• Authors: Trindade, Pablo; Loiola, Erick Correia; Gasparotto, Juciano; Ribeiro, Camila Tiefensee; Cardozo, Pablo Leal; Devalle, Sylvie; Salerno, José Alexandre; Ornelas, Isis Moraes; Ledur, Pitia Flores; Ribeiro, Fabiola Mara; Ventura, Ana Lucia Marques; Moreira, José Claudio Fonseca; Gelain, Daniel Pens; Porciúncula, Lisiane Oliveira; Rehen, Stevens Kastrup
• Is Part Of: Glia. Volume 68:Issue 7(2020)
• Page Start: 1396
• Page End: 1409
• Publication Date: 2020-01-31
• Subjects: astrogliosis -- cytokines -- induced pluripotent stem cells -- neuroinflammation -- reactive astrocytes; Neuroglia -- Periodicals; Neurology -- Periodicals; 611.0188
• DOI: 10.1002/glia.23786
• Languages: English
• ISSNs: 0894-1491

Abstract

Abstract: Astrogliosis comprises a variety of changes in astrocytes that occur in a context‐specific manner, triggered by temporally diverse signaling events that vary with the nature and severity of brain insults. However, most mechanisms underlying astrogliosis were described using animals, which fail to reproduce some aspects of human astroglial signaling. Here, we report an in vitro model to study astrogliosis using human‐induced pluripotent stem cells (iPSC)‐derived astrocytes which replicate temporally intertwined aspects of reactive astrocytes in vivo. We analyzed the time course of astrogliosis by measuring nuclear translocation of NF‐kB, production of cytokines, changes in morphology and function of iPSC‐derived astrocytes exposed to TNF‐α. We observed NF‐kB p65 subunit nuclear translocation and increased gene expression of IL‐1β, IL‐6, and TNF‐α in the first hours following TNF‐α stimulation. After 24 hr, conditioned media from iPSC‐derived astrocytes exposed to TNF‐α exhibited increased secretion of inflammation‐related cytokines. After 5 days, TNF‐α‐stimulated cells presented a typical phenotype of astrogliosis such as increased immunolabeling of Vimentin and GFAP and nuclei with elongated shape and shrinkage. Moreover, ~50% decrease in aspartate uptake was observed during the time course of astrogliosis with no evident cell damage, suggesting astroglial dysfunction. Together, our results indicate that human iPSC‐derived astrocytes reproduce canonical events associated with astrogliosis in a time dependent fashion. The approach described here may contribute to a better understanding of mechanisms governing human astrogliosis with potential applicability as a platform to uncover novel biomarkers and drug targets to prevent or mitigate astrogliosis associated with human brain disorders. Main Points: TNF‐α triggers astrogliosis in human induced pluripotent stem cells‐derived astrocytes. Short‐term TNF‐α exposure causes NF‐kB translocation and increases cytokines secretion. Long‐term TNF‐α exposure increases GFAP, Vimentin, and astrocyte polarization and decreases aspartate uptake.