Signalling mechanism in injured astrocytes activated by neurotrophins.

ANDREA BEATRÍZ CRAGNOLINI; DANIEL MASCÓ

Congreso; FALAN, Federation of Latin American and Caribbean Neuroscience Meeting; 2016

Federation of Latin American and Caribbean Neuroscience Meeting

Astrocytes are a heterogeneous population of glial cells that react to all kind of brain insults through a process referred to as astrogliosis. Reactive astrocytes are characterized by an increase in proliferation, size, migration to the injured zone and release of a plethora of chemical mediators such as NGF and BDNF. We have previously shown that the neurotrophic receptor p75NTR is upregulated in reactive astrocytes.The aim of this study was to determine the role of the neurotrophic receptors, p75NTR and TrkB.t in migration of astrocytes and to determine the signaling mechanism activated neurotrophin in injured astrocytes. We used an in vitro model (scratch wound) to induce injuries in astrocytes from different brain. This assay allowed us to assess several aspects of astrogliosis and distribution of neurotrophic receptors along the injured area. We found that a scratch injury in cultured astrocytes from different brain areas induces the expression of both receptors, p75NTR and TrkB.t and the co-rreceptor of p75NTR, sortilin. When astrocytes were treated with NGF the neurotrophin had a chemotactic effect on astrocytes (assessed in Boyden chambers) and induced wound closure but does not affect proliferation. Then we explore the signaling mechanism activated by p75NTR in injured astrocytes and treated with neurotrophins and we found that p75NTR can interact with sortilin. Our results are consistent with the idea that neurotrophin are able to modulate different aspects of gliosis after injury.