Glucocorticoids Decrease Astrocyte Numbers by Reducing Glucocorticoid Receptor Expression In Vitro and In Vivo
Glucocorticoids are stress hormones released from the adrenal cortex and their concentration is controlled by the hypothalamic–pituitary–adrenal axis. In this study, we investigated the effect of glucocorticoids on the number of astrocytes and glucocorticoid receptor (GR) expression in vitro and in...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Elsevier
2012-01-01
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| Series: | Journal of Pharmacological Sciences |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S1347861319305213 |
| _version_ | 1818035174063996928 |
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| author | Kazuhiro Unemura Toshiaki Kume Minami Kondo Yuki Maeda Yasuhiko Izumi Akinori Akaike |
| author_facet | Kazuhiro Unemura Toshiaki Kume Minami Kondo Yuki Maeda Yasuhiko Izumi Akinori Akaike |
| author_sort | Kazuhiro Unemura |
| collection | DOAJ |
| description | Glucocorticoids are stress hormones released from the adrenal cortex and their concentration is controlled by the hypothalamic–pituitary–adrenal axis. In this study, we investigated the effect of glucocorticoids on the number of astrocytes and glucocorticoid receptor (GR) expression in vitro and in vivo. Proliferation of cultured astrocytes was reduced following treatment with corticosterone and dexamethasone for 72 h. Corticosterone and dexamethasone also reduced GR expression in astrocytes. RU486, a GR antagonist, inhibited the reduction in both astrocyte prolifer ation and GR expression. Furthermore, GR knockdown by siRNA inhibited astrocyte proliferation. We also examined the effect of excessive glucocorticoid release on GR expression and the number of astrocytes in vivo by administering adrenocorticotropic hormone to rats for 14 days. GR expression was reduced in the prefrontal cortex and hippocampus and the number of astrocytes was reduced in the frontal cortex. Overall, our results suggest that glucocorticoids decrease the number of astrocytes by reducing GR expression. Keywords:: glucocorticoid, astrocyte, glucocorticoid receptor, adrenocorticotropic hormone (ACTH) |
| first_indexed | 2024-12-10T06:50:51Z |
| format | Article |
| id | doaj.art-fb5768463c954b1cbf4f3bece583c0ae |
| institution | Directory Open Access Journal |
| issn | 1347-8613 |
| language | English |
| last_indexed | 2024-12-10T06:50:51Z |
| publishDate | 2012-01-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Journal of Pharmacological Sciences |
| spelling | doaj.art-fb5768463c954b1cbf4f3bece583c0ae2022-12-22T01:58:34ZengElsevierJournal of Pharmacological Sciences1347-86132012-01-0111913039Glucocorticoids Decrease Astrocyte Numbers by Reducing Glucocorticoid Receptor Expression In Vitro and In VivoKazuhiro Unemura0Toshiaki Kume1Minami Kondo2Yuki Maeda3Yasuhiko Izumi4Akinori Akaike5Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida-shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, JapanDepartment of Pharmacology, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida-shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, JapanDepartment of Pharmacology, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida-shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, JapanDepartment of Pharmacology, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida-shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, JapanDepartment of Pharmacology, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida-shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, JapanDepartment of Pharmacology, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida-shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan; Corresponding author. aakaike@pharm.kyoto-u.ac.jp on April 28, 2012 (in advance)Glucocorticoids are stress hormones released from the adrenal cortex and their concentration is controlled by the hypothalamic–pituitary–adrenal axis. In this study, we investigated the effect of glucocorticoids on the number of astrocytes and glucocorticoid receptor (GR) expression in vitro and in vivo. Proliferation of cultured astrocytes was reduced following treatment with corticosterone and dexamethasone for 72 h. Corticosterone and dexamethasone also reduced GR expression in astrocytes. RU486, a GR antagonist, inhibited the reduction in both astrocyte prolifer ation and GR expression. Furthermore, GR knockdown by siRNA inhibited astrocyte proliferation. We also examined the effect of excessive glucocorticoid release on GR expression and the number of astrocytes in vivo by administering adrenocorticotropic hormone to rats for 14 days. GR expression was reduced in the prefrontal cortex and hippocampus and the number of astrocytes was reduced in the frontal cortex. Overall, our results suggest that glucocorticoids decrease the number of astrocytes by reducing GR expression. Keywords:: glucocorticoid, astrocyte, glucocorticoid receptor, adrenocorticotropic hormone (ACTH)http://www.sciencedirect.com/science/article/pii/S1347861319305213 |
| spellingShingle | Kazuhiro Unemura Toshiaki Kume Minami Kondo Yuki Maeda Yasuhiko Izumi Akinori Akaike Glucocorticoids Decrease Astrocyte Numbers by Reducing Glucocorticoid Receptor Expression In Vitro and In Vivo Journal of Pharmacological Sciences |
| title | Glucocorticoids Decrease Astrocyte Numbers by Reducing Glucocorticoid Receptor Expression In Vitro and In Vivo |
| title_full | Glucocorticoids Decrease Astrocyte Numbers by Reducing Glucocorticoid Receptor Expression In Vitro and In Vivo |
| title_fullStr | Glucocorticoids Decrease Astrocyte Numbers by Reducing Glucocorticoid Receptor Expression In Vitro and In Vivo |
| title_full_unstemmed | Glucocorticoids Decrease Astrocyte Numbers by Reducing Glucocorticoid Receptor Expression In Vitro and In Vivo |
| title_short | Glucocorticoids Decrease Astrocyte Numbers by Reducing Glucocorticoid Receptor Expression In Vitro and In Vivo |
| title_sort | glucocorticoids decrease astrocyte numbers by reducing glucocorticoid receptor expression in vitro and in vivo |
| url | http://www.sciencedirect.com/science/article/pii/S1347861319305213 |
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