| Full text | |
| Author(s): |
Sales, Sayuri
[1]
;
Ureshino, Rodrigo Portes
[2]
;
dos Santos Pereira, Renato Tavares
[1]
;
Amaral Luna, Milene Schmidt
[1]
;
de Oliveira, Marcelo Pires
[2]
;
Yamanouye, Norma
[1]
;
Godinho, Rosely Oliveira
[2]
;
Smaili, Soraya Soubhi
[2]
;
Porto, Catarina Segreti
[2]
;
Francis Abdalla, Fernando Mauricio
[1]
Total Authors: 10
|
| Affiliation: | [1] Inst Butantan, Pharmacol Lab, BR-05503900 Sao Paulo - Brazil
[2] Univ Fed Sao Paulo, Dept Pharmacol, Escola Paulista Med, Sao Paulo - Brazil
Total Affiliations: 2
|
| Document type: | Journal article |
| Source: | Life Sciences; v. 86, n. 21-22, p. 832-838, MAY 22 2010. |
| Web of Science Citations: | 16 |
| Abstract | |
Aims: The aim of the present study was to investigate the effects of different periods of ovariectomy and 17 beta-estradiol replacement on apoptotic cell death and expression of members of the Bcl-2 family in the rat hippocampus. Main methods: Hippocampi were obtained from rats in proestrus, ovariectomized (15 days, 21 days and 36 days), ovariectomized for 15 days and then treated with 17 beta-estradiol for 7 or 21 days, and rats ovariectomized and immediately treated with 17 beta-estradiol for 21 days. The expression of Bcl-2 and Bax and the number of apoptotic cells were determined. Key findings: Ovariectomy decreased Bcl-2 expression and increased Bax expression and the number of apoptotic cells. Replacement with 17 beta-estradiol (21 days) throughout the post-ovariectomy period reduced the number of apoptotic cells to the control levels, and prevented the effects of ovariectomy on Bax expression, but only partially restored the Bcl-2 expression. After 15 days of ovariectomy. the replacement with 17 beta-estradiol for 21 days, but not for 7 days, restored the Bcl-2 and Bax expression and the percentage of apoptotic cells to the levels found in the proestrus control. Significance: The present results show that a physiological concentration of 17 beta-estradiol may help maintain long-term neuronal viability by regulating the expression of members of the Bcl-2 family. Even after a period of hormonal deprivation, treatment with 17 beta-estradiol is able to restore the expression of Bax and Bcl-2 to control levels, but the duration of the treatment is a key factor to obtain the desired effect. These data provide new understanding into the mechanisms contributing to the neuroprotective action of estrogen. (C) 2010 Elsevier Inc. All rights reserved. (AU) | |
| FAPESP's process: | 03/10132-0 - Estrogen and colinergic muscarinic neurotransmission: expression of receptors, intracellular signaling and its interactions in the central nervous system and in the male reproductive tract |
| Grantee: | Catarina Segreti Porto |
| Support Opportunities: | PRONEX Research - Thematic Grants |