title: Neuroprotection and protein damage prevention by estradiol replacement in rat hippocampal slices exposed to oxygen-glucose deprivation.
abstract: 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.
authors.affiliation: Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, UFRGS, 90035-003, Porto Alegre, RS, Brazil.
authors.forename: Helena
authors.initials: H
authors.lastname: Cimarosti
authors.forename: Ionara R
authors.initials: IR
authors.lastname: Siqueira
authors.forename: Lauren L
authors.initials: LL
authors.lastname: Zamin
authors.forename: Melissa
authors.initials: M
authors.lastname: Nassif
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Balk
authors.forename: Rudimar
authors.initials: R
authors.lastname: Frozza
authors.forename: Carla
authors.initials: C
authors.lastname: Dalmaz
authors.forename: Carlos Alexandre
authors.initials: CA
authors.lastname: Netto
authors.forename: Christianne
authors.initials: C
authors.lastname: Salbego
mesh_terms: 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
chemical_list: 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