光敏感膜透需要光敏感剂和脂质之间的接触依赖反应
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
概括
光敏剂和光通过光氧化使脂质膜透. 直接的光敏感剂-脂质接触对化物形成至关重要,这促使膜透和细胞死亡.
科学领域:
- 生物化学
- 膜生物物理
- 摄影化学
背景情况:
- 已知脂质氧化机制,但光敏感剂介导的膜透途径尚不清楚.
- 光敏剂 (PS) 和光诱导脂质氧化,影响膜完整性.
- 了解这些过程对于光动力疗法 (PDT) 的应用至关重要.
研究的目的:
- 阐明光敏剂诱导的脂质光氧化的化学步骤.
- 描述光氧化产品及其对脂质双层的影响.
- 将光敏剂-脂质相互作用与膜透和细胞杀死效率相关联.
主要方法:
- 使用基于的光敏剂 (甲蓝,MB和DO15) 具有不同的脂质局部化.
- 研究的1 - 棕基-2- 基- 糖基-3- 胆 (POPC) 和多不和脂质脂质体.
- 使用分析技术量化的脂质氧化产物 (氧化物,酒精,类,化物).
主要成果:
- 具有较高的脂质局部化,透膜明显高于MB.
- 脂类化物被确定为与膜透相关的关键产品.
- 直接接触光敏剂和脂质促进了氧化产品的形成,特别是化物.
结论:
- 直接的光敏剂-脂质相互作用对于有效的脂质氧化和生成至关重要.
- 化物形成显著降低了水透膜的能量屏障.
- 光敏感剂的膜结合亲和度与其在PDT中的细胞杀伤效率直接相关.
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