光感受性膜の浸透は,光感受剤と脂質の接触依存反応を必要とする
Isabel O L Bacellar1,2, Maria Cecilia Oliveira3, Lucas S Dantas1
1Departamento de Bioquímica, Instituto de Química , Universidade de São Paulo , Avenida Prof. Lineu Prestes 748 , São Paulo , SP , Brazil , 05508-000.
Journal of the American Chemical Society
|July 11, 2018
まとめ
光感受剤と光は,光酸化によって脂質膜を透過させる. 光敏感剤と脂質との直接的な接触はアルデヒド形成に不可欠であり,それは膜浸透と細胞死を引き起こす.
科学分野:
- 生物化学
- 膜生物物理学
- 写真化学
背景:
- 脂質酸化メカニズムは知られていますが,光敏感剤媒介の膜浸透経路は不明です.
- 光敏感剤 (PS) と光は脂質酸化を誘導し,膜の完全性に影響する.
- これらのプロセスを理解することは,光ダイナミック療法 (PDT) のアプリケーションにとって極めて重要です.
研究 の 目的:
- fotosensitizer 誘発された脂質の光酸化の化学的ステップを明らかにする.
- 光酸化製品の特徴と,脂質二層への影響
- 光敏感剤と脂質の相互作用と膜の浸透性と細胞破壊効率を相関させる.
主な方法:
- フェノチアジニウムベースの光敏感剤 (メチレンブルー,MB,DO15) が使用され,脂質コロカライゼーションが異なる.
- 調べられた1-パルミトイル-2-オレイル-スン-グリセロ-3-フォスホリン (POPC) と多不飽和脂質リポソーム.
- 分析技術を用いた脂質酸化製品 (水酸化物,アルコール,ケトン,アルデヒド) の量化
主要な成果:
- DO15は,より高い脂質コロカライゼーションで,MBよりもはるかに浸透した膜です.
- 脂質アルデヒドは,膜浸透に関連した主要な製品として特定されました.
- 光敏感剤と脂質の直接接触により,酸化製品,特にアルデヒドの形成が促進された.
結論:
- 効率的な脂質酸化とアルデヒド生成には,直接の光敏感剤と脂質の相互作用が不可欠である.
- アルデヒドの形成は,膜を通過する水のエネルギーバリアを大幅に低下させます.
- 光敏感剤の膜結合親和性は,PDTにおける細胞破壊効果と直接相関しています.
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