ビタミンCが誘発した脂質ヒドロペロキシドの分解により,内生性遺伝子毒素に変化する
1Center for Cancer Pharmacology, University of Pennsylvania, 1254 BRB II/III, 421 Curie Boulevard, Philadelphia, PA 19104-6160, USA.
Science (New York, N.Y.)
|June 16, 2001
まとめ
ビタミンC (アスコルビック酸) のサプリメントは,がんを予防しない可能性があります. 酸化脂肪からDNAを損傷する化合物を生成し,がん予防研究における無効性を説明する可能性がある.
科学分野:
- バイオケミストリー バイオケミストリー
- 分子生物学は分子生物学である.
- がん研究 がん研究
背景:
- ビタミンCを含む食中の抗酸化物質は,がん予防のために研究されています.
- ビタミンCは,がんの化学予防試験において無効であることが示されています.
- ビタミンCの潜在的プロ酸化効果について懸念があります.
研究 の 目的:
- ビタミンCが癌の化学予防に失敗するメカニズムを調査する.
- ビタミンCが脂質水酸化物からDNA反応性化合物を生成できるかどうかを判断する.
主な方法:
- ビタミンCと脂質水酸化物との相互作用の分析.
- 形成されたDNA反応性電ophilesの識別.
- 反応産物の遺伝子毒性可能性の評価.
主要な成果:
- ビタミンCは,脂質水酸化物分解を誘導する.
- DNAに反応する二機能性電ophilesの形成: 4-oxo-2-nonenal, 4,5-epoxy-2(E) -decenal, そして 4-hydroxy-2-nonenal.
- 4,5-Epoxy-2(E) -decenalは,DNAにおける変異性エテノ-2'-デオキシアデノシンの前駆体である.
結論:
- ビタミンCは,移行金属イオンとは独立して,脂質水酸化物から遺伝子毒素を生成することができます.
- このメカニズムは,がんの化学予防におけるビタミンCの有効性の欠如を説明するかもしれない.
さらに関連する動画
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