遺伝子の調節とDNAの損傷は,老化する人間の脳で起こります
Tao Lu1, Ying Pan, Shyan-Yuan Kao
1Department of Neurology and Division of Neuroscience, The Children's Hospital and Harvard Medical School, Enders 260,300 Longwood Avenue, Boston, Massachusetts 02115, USA.
Nature
|June 11, 2004
まとめ
認知機能の低下の原因である脳の老化は,成人期の初期に始まります. 40歳以降の前頭皮質における特定の遺伝子発現変化とDNA損傷は,このプロセスの開始を示しています.
科学分野:
- 神経科学は神経科学である.
- 遺伝学 遺伝学とは
- 老化に関する研究
背景:
- 人間の脳の老化は,認知機能の低下とアルツハイマー病に関連しています.
- 脳の老化の正確な発症時期は不明である.
- 早期の分子変化を特定することは,年齢に関連する認知障害を理解するために不可欠です.
研究 の 目的:
- 脳の老化が始まる時期を判断する.
- 早期の脳老化に関連した分子マーカーを特定する.
- 年齢に関連する遺伝子発現の変化におけるDNA損傷の役割を調査する.
主な方法:
- 人間の前頭皮質の転写プロファイリングは,幅広い年齢 (26-106歳) にわたって行われます.
- シナプス性可塑性,ミトコンドリア機能,ストレス反応に関連する遺伝子発現パターンの分析.
- 特定の遺伝子プロモーターにおけるDNA損傷と修復機構の評価.
主要な成果:
- シナプス性可塑性,膀移動,ミトコンドリア機能に関与する遺伝子のセットは,40歳以降,発現が減少したことを示した.
- この減少には,ストレス反応,抗酸化物質,DNA修復遺伝子の誘導が続いた.
- 高齢な皮質のダウンレギュレートされた遺伝子のプロモーターでDNA損傷の増加が観察され,基礎切除修復が損なわれた.
結論:
- 特定の遺伝子発現の変化とDNAの損傷によって特徴づけられる脳老化は,成人の早期に始まります.
- DNAの損傷は,学習,記憶,および神経細胞の生存に不可欠な遺伝子の発現を選択的に減少させる可能性があります.
- これらの発見は,成人期半ばから始まる脳の老化のための分子プログラムを示唆しています.
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