Neuroprotection and protein damage prevention by estradiol replacement in rat hippocampal slices exposed to oxygen-glucose deprivation.
Here we investigated the effects of estradiol replacement in ovariectomized female rats using hippocampal slices exposed to oxygen-glucose deprivation (OGD). OGD induced lactate dehydrogenase (LDH) release to the incubation medium, what was assumed as a parameter of cellular death. In the estradiol-treated group the LDH release was markedly decreased by 23% as compared to the vehicle-treated group. In attempt to study a possible mechanism by which estradiol acts, we investigated some parameters of oxidative stress. In both vehicle-treated and estradiol-treated groups, OGD significantly increased the free radical production by 34% and 16%, respectively, although no significant differences on total antioxidant capacity were observed. Interestingly, estradiol replacement prevented the significant reduction in tryptophan and tyrosine contents caused by OGD observed in vehicle-treated animals. Our results show that estradiol replacement in ovariectomized female rats decreases cellular susceptibility to an ischemic-like injury and suggest a role for the hormone on protein damage prevention.
Cimarosti
Helena
H
Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, UFRGS, 90035-003, Porto Alegre, RS, Brazil.
Siqueira
Ionara R
IR
Zamin
Lauren L
LL
Nassif
Melissa
M
Balk
Rodrigo
R
Frozza
Rudimar
R
Dalmaz
Carla
C
Netto
Carlos Alexandre
CA
Salbego
Christianne
C
D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D004958:Estradiol / Q000378:metabolism / Q000494:pharmacology*; D015914:Estrogen Replacement Therapy; D005260:Female; D005609:Free Radicals / Q000378:metabolism; D005947:Glucose / Q000172:deficiency*; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D002534:Hypoxia, Brain / Q000378:metabolism* / Q000473:pathology; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000187:drug effects / Q000378:metabolism*; D018696:Neuroprotective Agents; D010052:Ovariectomy; D051381:Rats; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000378:metabolism; D014364:Tryptophan / Q000187:drug effects / Q000378:metabolism; D014443:Tyrosine / Q000187:drug effects / Q000378:metabolism
D000975:Antioxidants; D005609:Free Radicals; D009419:Nerve Tissue Proteins; D018696:Neuroprotective Agents; D017382:Reactive Oxygen Species; D014443:Tyrosine; D004958:Estradiol; D014364:Tryptophan; D007770:L-Lactate Dehydrogenase; D005947:Glucose