Brain-region specific responses of astrocytes to an in vitro injury and neurotrophins

MONTENEGRO, M; CRAGNOLINI,ANDRREA; MASCÓ, D.H. ,; FRIEDMAN,W

MOLECULAR AND CELLULAR NEUROSCIENCES.

ACADEMIC PRESS INC ELSEVIER SCIENCE

Lugar: Amsterdam; Año: 2018 vol. 88 p. 240 - 248

1044-7431

Astrocytes areaheterogeneous population ofglialcellsthatreact tobraininsultsthrough aprocessreferredtoas 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. The aim of this study was to determine whether there are brain region-associated responses of astrocytes to an injury and to the neurotrophins NGF and BDNF. We used the scratch injury model to study the closure of a wound inflicted on a monolayerofastrocytes obtained fromcortex,hippocampusorstriatum.Ourresults indicatethattheresponseof astrocytes to a mechanical lesion differ according to brain regions. Astrocytes from the striatum proliferate and repopulate the injury site more rapidly than astrocytes from cortex or hippocampus. We found that the scratch injury induced the upregulation of neurotrophin receptor p75NTR and TrkB.t inastrocytes from all brainregions studied. When astrocytes from all regions were treated with NGF, the neurotrophin induced migration of the astrocytes (assessed in Boyden chambers) and induced wound closure but did not affect proliferation. In contrast, BDNF induced wound closure but only in astrocytes from striatum. Our overall findings show the heterogeneity in astrocyte functions based on their brain region of origin, and how this functional diversity may determine their responses to an injury and to neurotrophins.