吸収されたアルミニウムはミトコンドリアに蓄積する
Mirna Rita Tenan1, Stefano Jacopo Mandriota1, André-Pascal Sappino1
1Laboratoire de Cancérogenèse Environnementale, Fondation des Grangettes, Chêne-Bougeries 1224, Switzerland.
まとめ
この研究は,毎日吸収される有毒アルミニウムは,哺乳類のミトコンドリア内に蓄積し,エンドプラズマ網やエンドソームには蓄積しないことを明らかにしています. この発見は,摂取されたアルミニウムの細胞下部位置を明らかにします.
科学分野:
- 毒理学について
- 細胞生物学
- 生物化学
背景:
- アルミニウムは有毒な元素で,様々な製品から毎日広く吸収され,ヒトに発がんを引き起こす可能性がある.
- 吸収されたアルミは,主にトランスファーリン (TF) 経由で全身循環し,人の臓器に蓄積する.
- 内部化されたアルミニウムの正確な細胞下部位は不明であるが,以前は,核の近くの粒状網状臓器に蓄積すると考えられていた.
研究 の 目的:
- 細胞の吸収後にアルミニウムが蓄積する特定の細胞下臓器を特定する.
- エンドプラズマ網膜 (ER) やエンドソームがアルミニウム蓄積の主な場所であるかどうかを調査する.
- アルミニウムの捕獲に 責任を負う細胞の正確な区間を決定する.
主な方法:
- ルモガリオン染色 (アルミニウム検出用) とオルガネル特異の免疫光を組み合わせたプロトコルを開発した.
- アルミニウム塩化物 (AlCl3) に暴露された使用されたMCF10Aヒト乳腺上皮細胞.
- エンドプラズマ網膜 (カルレチクリン) とトランスファーリン受容体1 (TFR1) のマーカーとアルミニウム局所化を比較し,ミトコンドリア探知器MitoTrackerで共局所化した.
主要な成果:
- アルミニウムはカルレチクリンと共局所化していないので,ERは主要な蓄積部位ではないことを示しています.
- アルミニウムはトランスファーリン受容体1 (TFR1) と同局化していないため,内分子が内分化に関与している可能性は低い.
- アルミニウム特異のLumogallion光は,ヒトおよびマウンの乳頭上皮細胞,特に周核領域で,MitoTracker光と密接に同定されています.
結論:
- 細胞内のアルミニウム蓄積の主要な場所は,エンドプラズマ網とエンドソームではありません.
- 強い実験的証拠は,アルミニウムは細胞吸収時に哺乳類のミトコンドリアに蓄積することを示しています.
- この研究は,内蔵されたアルミニウムの細胞下部位を明らかにし,ミトコンドリアを重要な臓器細胞として特定した.
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