Ascorbate uptake is decreased in the hippocampus of ageing rats.
Ascorbate, an intracellular antioxidant, has been considered critical for neuronal protection against oxidant stress, which is supported especially by in vitro studies. Besides, it has been demonstrated an age-related decrease in brain ascorbate levels. The aims of the present study were to investigate ascorbate uptake in hippocampal slices from old Wistar rats, as well as its neuroprotective effects in in vitro and in vivo assays. Hippocampal slices from male Wistar rats aged 4, 11 and 24 months were incubated with radiolabeled ascorbate and incorporated radioactivity was measured. Hippocampal slices from rats were incubated with different concentrations of ascorbate and submitted to H(2)O(2)-induced injury, cellular damage and S100B protein levels were evaluated. The effect of chronic administration of ascorbate on cellular oxidative state and astrocyte biochemical parameters in the hippocampus from 18-months-old Wistar rats was also studied. The ascorbate uptake was decreased in hippocampal slices from old-aged rats, while supplementation with ascorbate (2 weeks) did not modify any tested oxidative status in the hippocampus and the incubation was unable to protect hippocampal slices submitted to oxidative damage (H(2)O(2)) from old rats. Our data suggest that the decline of ascorbate uptake might be involved in the brain greater susceptibility to oxidative damage with advancing age and both in vitro and vivo assays suggest that ascorbate supplementation did not protect hippocampal cells.
Departamento de Farmacologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil. ionara@ufrgs.br
Ionara Rodrigues
IR
Siqueira
Viviane Rostirolla
VR
Elsner
Marina Concli
MC
Leite
Cláudia
C
Vanzella
Felipe dos Santos
Fdos S
Moysés
Christiano
C
Spindler
Graça
G
Godinho
Cíntia
C
Battú
Suzana
S
Wofchuk
Diogo Onofre
DO
Souza
Carlos Alberto
CA
Gonçalves
Carlos Alexandre
CA
Netto
D000375:Aging / Q000378:metabolism*; D000818:Animals; D001205:Ascorbic Acid / Q000378:metabolism*; D006624:Hippocampus / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000494:pharmacology; D066298:In Vitro Techniques; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism
D017392:Thiobarbituric Acid Reactive Substances; D006861:Hydrogen Peroxide; D001205:Ascorbic Acid