| Project/Area Number |
14572071
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Biological pharmacy
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| Research Institution | Tokyo University of Pharmacy and Life Sciences |
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Principal Investigator |
HIRATSUKA Akira Tokyo University of Pharmacy and Life Sciences, School of Pharmacy, Professor, 薬学部, 教授 (20165179)
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| Project Period (FY) |
2002 – 2005
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| Project Status |
Completed (Fiscal Year 2005)
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| Budget Amount *help |
¥3,000,000 (Direct Cost: ¥3,000,000)
Fiscal Year 2005: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 2004: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 2003: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 2002: ¥900,000 (Direct Cost: ¥900,000)
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| Keywords | 4-hydroxynonenal / Clone 9 / cell toxicity / glutathione S-transferase / hydroperoxide / stereoselectivity / metabolism / detoxification / エナンチオマー / 立体選択性 / グルタチオンS-トランスフェラーゼ / グルタチオン抱合 / 還元反応 / 細胞毒性 / PC12 / ラット / 脂質過酸化 / Clone 9 |
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| Research Abstract |
Racemic 4-hydroxy-2(E)-nonenal (HNE) is known as a reactive and highly toxic product released from biomembranes by lipid peroxidation in vivo. Until the present, all previous studies on the cytotoxic effects of HNE were performed using its racemate. In this study, the toxicities of (S)- and (R)-HNE were examined in rat Clone 9 cells. IC_<50> values for inhibition of cell growth were 15.6 μM for (R)-HNE and 5.1 μM for (S)-HNE. To estimate the cytotoxic response, Clone 9 cells were separately incubated with (S)- and (R)-HNE, stained with Annexine V-FITC or propidium iodide, and analyzed by flow cytometry. These results suggest that (S)-HNE is a much more potent agent than (R)-HNE for cell growth inhibition and induction of apoptosis and also that cell death via apoptosis and via necrosis occurs only at lower (<10 μM) and higher (>20 μM) concentrations of HNEs, respectively. This study also showed that in rat Clone 9 cell cytosol, FINE enantiomers were detoxified (S)-preferentially by GSH conjugation and that several classes of GST existed in rat Clone 9 cells. However, no immunostainable protein was detected in the cell cytosol by Western blot analysis using the anti-rGSTA4-4 antibody. The absence of the rGSTA4-4 isoform could be responsible for the observed low Vmax/Km value in the GSH conjugation of HNE enantiomers in Clone 9 cell cytosol compared with a high Vmax/Km value observed for that in rat liver cytosol. The cytotoxic study in rat Clone 9 cells revealed that (S)-HNE displayed significant toxicity in the cell line studied, with the IC_<50> value in the low micromolar range. Thus, based on the results presented here, enantiopreferential detoxification of HNE enantiomers in Clone 9 cells is unlikely to be an important factor in determining their response to (S)-preferential cytotoxicity.
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