Abstract
Hippocampus is one of the most vulnerable tissues to glucocorticoid (GC). In the present study, we demonstrate that dexamethasone (DEX), a synthetic GC, induces apoptotic cell death in hippocampal progenitor HiB5 cells without any additional insult. Interestingly, expression of 27-kDa heat shock protein (HSP27) was markedly induced by DEX in time- and dose-dependent manners. This induction was dependent on the production of reactive oxygen species (ROS), suggesting that DEX-evoked oxidative damage to HiB5 cells is responsible for the HSP27 induction. To evaluate a possible role of HSP27, we generated two mutant HiB5 cell lines, in which expression of HSP27 was inhibited or enhanced by the over-expression of HSP27 cDNA with antisense or sense orientation (AS-HSP27 and S-HSP27, respectively). DEX-induced apoptotic cell population was significantly increased in AS-HSP27 HiB5 cells and evidently decreased in S-HSP27 cells. These results indicate that HSP27 protects hippocampal progenitor cells from GC-induced apoptotic cell death.
Original language | English |
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Pages (from-to) | 1751-1758 |
Number of pages | 8 |
Journal | Biochemical and Biophysical Research Communications |
Volume | 338 |
Issue number | 4 |
DOIs | |
State | Published - 30 Dec 2005 |
Keywords
- Apoptosis
- Glucocorticoid
- HSP27
- HiB5
- Hippocampal progenitor