在整个还原过程中,Cr (vi) 在一个反转的六角相中永久地与脂质二层结合
Michal Nowakowski1, Anna Wiśniewska-Becker2, Joanna Czapla-Masztafiak1
1Institute of Nuclear Physics Polish Academy of Sciences PL-31342 Krakow Poland wojciech.kwiatek@ifj.edu.pl.
RSC advances
|June 23, 2023
概括
(VI) 通过在膜内减少,很容易损害细胞. 这项研究表明,与脂质结构结合,特别影响倒立六角相,突出其细胞毒性机制.
科学领域:
- 生物化学 生物化学
- 材料科学 材料科学 材料科学
- 毒理学 毒理学 毒理学
背景情况:
- 六价 (Cr(VI)) 是一种强有力的致癌物,很容易穿透细胞脂质膜.
- 细胞内的Cr(VI) 降解到较低的氧化状态会产生危险的基因物种.
- 细胞膜是细胞功能和与外部物质相互作用的关键接口.
研究的目的:
- 研究Cr(VI与模型细胞膜,特别是脂质体和由甲胺 (PE) 组成的倒立六角相结构的相互作用.
- 量化在暴露和透析后在脂质结构中保留的数量和氧化状态.
- 评估Cr(VI) 对不同脂质膜相的内部秩序和流动性的影响.
主要方法:
- 使用PE制备脂质体和反向六角相脂质结构.
- 将脂质膜暴露在受控度的Cr (VI) 中,然后进行广泛的透析.
- 使用X射线光/X射线吸收/电子偏磁共振 (XRF/XAS/EPR) 的综合方法进行分析.
- 测量内部膜秩序和流动性的变化,以应对Cr (VI) 暴露.
主要成果:
- 即使在长时间透析后,大量的Cr (III) 和Cr (VI) 仍然与脂质结构结合.
- 结合的数量随着更高的PE含量和脂质混合物中不和脂肪酸键 (-C=C-) 的存在而增加.
- (VI) 的暴露导致了较少流动性膜的内膜秩序下降,以及较多流动性膜的轻微变化.
- 倒置的六角形相对Cr(VI) 诱导的氧化有更大的敏感性,而不是状相.
结论:
- 脂质结构,特别是倒置六角相中的脂质结构,在暴露后保留,表明细胞内积累的机制.
- 的结合亲和力受脂质组成的影响,特别是PE含量和脂肪酸和度.
- 脂质相对的差异性敏感性表明膜结构在Cr (VI) 细胞毒性中起着作用.
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