Glutamate uptake in cultured astrocytes depends on age: a study about the effect of guanosine and the sensitivity to oxidative stress induced by H(2)O(2).
Relatively few studies have been conducted to investigate the relationship between glutamate and development and/or aging. Rat cortical astrocyte cultures were used as a model to investigate glutamate uptake during development. The immunocontent of the markers glial fibrillary acidic protein (GFAP) and S100B increased, while basal secretion of S100B decreased, in astrocytes from 10 to 40 days in vitro (DIV). Basal glutamate uptake increased with age. Exposure to hydrogen peroxide decreased glutamate uptake more potently at 40 than 10 DIV. Moreover, 40 DIV astrocytes showed earlier loss of integrity (at 6 h) than 10 DIV astrocytes (at 24 h) after H(2)O(2) exposure. Addition of guanosine stimulated glutamate uptake only in 10 DIV astrocytes. The present work shows that mature astrocytes in culture present some neurochemical alterations also observed in astrocytes of aged animals. These results can contribute to the understanding of some consequences of the excitotoxicity and oxidative stress during brain aging.
Gottfried
Carmem
C
Departamento de Ciências Fisiológicas, Faculdade de Biociências, Pontifi;cia Universidade Católica do Rio Grande do Sul, PUCRS, RS, Porto Alegre, Brazil. cacg@terra.com.br
Tramontina
Francine
F
Gonçalves
Daniela
D
Gonçalves
Carlos A
CA
Moriguchi
Emilio
E
Dias
Renato D
RD
Wofchuk
Susana T
ST
Souza
Diogo Onofre
DO
D000375:Aging / Q000378:metabolism*; D000818:Animals; D001253:Astrocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D018698:Glutamic Acid / Q000378:metabolism*; D006151:Guanosine / Q000494:pharmacology*; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D009414:Nerve Growth Factors / Q000378:metabolism; D018384:Oxidative Stress; D051381:Rats; D017208:Rats, Wistar; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins / Q000378:metabolism
D005904:Glial Fibrillary Acidic Protein; D009414:Nerve Growth Factors; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins; C579158:S100b protein, rat; D006151:Guanosine; D018698:Glutamic Acid; D006861:Hydrogen Peroxide