Localization of lipid microdomains and thermal phenomena in murine stratum corneum and isolated membrane complexes: an electron spin resonance study.
Localization of lipid microdomains and thermal phenomena in murine stratum corneum and isolated membrane complexes: an electron spin resonance study.
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小鼠角质层和分离膜复合物中脂质微区和热现象的定位：电子自旋共振研究。
DOI：
10.1111/1523-1747.ep12478052
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发表时间：
1990
期刊：
影响因子：
--
通讯作者：
Elias,PM
中科院分区：
文献类型：
--
作者：
Rehfeld,SJ;Plachy,WZ;Hou,SY;Elias,PM
角质层的细胞间区域可以以缺乏细胞质组分的膜复合物（细胞间脂质和相邻的角质层包膜）的形式分离。在这项研究中，温度诱导的相变和相应的脂质结构域重组分离角质层（SC）片和SC膜复合物（SCM）确定使用电子自旋共振（ESR）自旋探针技术。自旋探针全氘代二叔丁基氮氧自由基（pdDTBN）在SC和SCM显示不太明确的生理相变中的SCM和一个更极性的脂质域在SC。然而，ESR结果表明，共存的高度有序的域（固定自旋探针）和粘性较低的域在完整的SC，坚持在SCM。高于1020 °C，自旋探针溶解在SC和SCM中的高度无序（各向同性）脂质结构域中。在溶剂提取的SC和SCM中，自旋探针溶解在与角质细胞包膜复合的脂质相关的高度有序的亲脂性结构域中，并且在-23° C至60° C之间不显示热转变。此外，移动的自旋探针的量与残余脂质的量相关。一个意想不到的发现是溶剂提取的SCM中自旋探针的明显减少，这表明这些位点存在以前未认识到的自由基还原机制。自旋探针的迁移率时，溶解在模型脂质，非羟基，羟基含有神经酰胺和胆固醇油酸酯，显着不同，从那些观察到SC或SCM。这些研究证明了ESR用于角质层中脂质微环境的定位和表征的有用性。
The intercellular region of the stratum corneum can be isolated in the form of membrane complexes (intercellular lipids and adjacent cornified envelopes) which are devoid of the cytoplasmic components. In this study the temperature induced phase transitions and corresponding lipid domain reorganization in isolated stratum corneum (SC) sheets and SC membrane complexes (SCM) were determined using the electron spin resonance (ESR) spin probe technique. The spin probe perdeuterated di-tert-butyl nitroxide (pdDTBN) in SC and SCM revealed less well-defined physiologic phase transitions in the SCM and a more polar lipid domain in SC. However, the ESR results show the coexistence of highly ordered domains (immobilized spin probe) and less viscous domains in intact SC, which persist in SCM. Above ≍ 20°C the spin probe is dissolved in a highly disordered (isotropic) lipid domain in both SC and SCM. In both solvent extracted SC and SCM, the spin probe is dissolved in a highly ordered lipophilic domain associated with the lipids complexed to the corneocyte envelope and exhibiting no thermal transitions between -23° to 60° C. Further, the amount of mobile spin probe is related to the amount of residual lipid. An unexpected finding was the apparent reduction of the spin probe in solvent extracted SCM, suggesting the presence of a previously unrecognized free radical reducing mechanism in these sites. The mobilities of the spin probe when dissolved in model lipids, non-hydroxy, and hydroxy containing ceramides and cholesteryl oleate, differed significantly from those observed in sc or SCM. These studies demonstrate the usefulness of ESR for the localization and characterization of lipid microenvironments in the stratum corneum.