title: Physical exercise increases GFAP expression and induces morphological changes in hippocampal astrocytes.
abstract: Physical exercise has an important influence on brain plasticity, which affects the neuron-glia interaction. Astrocytes are susceptible to plasticity, and induce and stabilize synapses, regulate the concentration of various molecules, and support neuronal energy metabolism. The aim of our study was to investigate whether physical exercise is capable of altering the morphology, density and expression of glial fibrillary acidic protein (GFAP) in astrocytes from the CA1 region of rat hippocampus. Thirteen male rats were divided in two groups: sedentary (n = 6) and exercise (n = 7). The animals in the exercise group were submitted to a protocol of daily physical exercise on a treadmill for four consecutive weeks. GFAP immunoreactivity was evaluated using optical densitometry and the morphological analyses were an adaptation of Sholl's concentric circles method. Our results show that physical exercise is capable of increasing the density of GFAP-positive astrocytes as well as the regional and cellular GFAP expression. In addition, physical exercise altered astrocytic morphology as shown by the increase observed in the degree of ramification in the lateral quadrants and in the length of the longest astrocytic processes in the central quadrants. Our data demonstrate important changes in astrocytes promoted by physical exercise, supporting the idea that these cells are involved in regulating neural activity and plasticity.
authors.affiliation: Departamento de Ciências Morfofisiológicas, Laboratório de Biologia Celular e Tecidual, Faculdade de Biociências, Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS), Avenida Ipiranga, 6681, Prédio 12C, Sala 104, Porto Alegre, RS, CEP 90619-900, Brazil.
authors.forename: Lisiani
authors.initials: L
authors.lastname: Saur
authors.forename: Pedro Porto Alegre
authors.initials: PP
authors.lastname: Baptista
authors.forename: Priscylla Nunes
authors.initials: PN
authors.lastname: de Senna
authors.forename: Mariana Fontoura
authors.initials: MF
authors.lastname: Paim
authors.forename: Patricia
authors.initials: P
authors.lastname: do Nascimento
authors.forename: Jocemar
authors.initials: J
authors.lastname: Ilha
authors.forename: Pamela Brambilla
authors.initials: PB
authors.lastname: Bagatini
authors.forename: Matilde
authors.initials: M
authors.lastname: Achaval
authors.forename: Léder Leal
authors.initials: LL
authors.lastname: Xavier
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000166:cytology* / Q000378:metabolism*; D002452:Cell Count; D005786:Gene Expression Regulation / Q000502:physiology*; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism*; D006624:Hippocampus / Q000166:cytology*; D008297:Male; D010805:Physical Conditioning, Animal / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D005904:Glial Fibrillary Acidic Protein