Preferential arrangement of lipids in the long-periodicity phase of a stratum corneum matrix model
Preferential arrangement of lipids in the long-periodicity phase of a stratum corneum matrix model
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DOI：
10.1194/jlr.m087106
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发表时间：
2018-12-01
影响因子：
6.5
通讯作者：
Bouwstra, Joke A.
中科院分区：
文献类型：
--
作者：
Beddoes, Charlotte M.;Gooris, Gert S.;Bouwstra, Joke A.
角质层的脂肪基质是最外层的皮肤，主要由神经酰胺、胆固醇和游离脂肪酸组成。这些脂质形成一个三层长周期相(LPP)，这是这一屏障所独有的。有关LPP的知识对于理解屏障功能是必不可少的。以往对LPP脂质模型的研究已经确定了主要脂质类别的位置，并表明很大一部分FFAs和神经酰胺酰链存在于中央区域。然而，精确的排列，如脂质亚类混合(单独或混合)和神经酰胺构象(延长或发夹)，仍不清楚。在这里，我们对游离脂肪酸和神经酰胺酰链进行了氢化，用傅里叶变换红外光谱研究了CD2和CH2之间的相互作用。不同链长的神经酰胺和游离脂肪酸并不在单独的结构域中，而是混合在一起。LPP中CD2-CD2脂链相互作用的数量比对称双层结构中的多，这表明神经酰胺主要采用扩展构象。LPP中央区有较短的FFAs。该模型探索角质层LPP的生物物理性质，以提高对该层屏障功能的理解。
The lipid matrix of the stratum corneum, the outermost skin layer, consists primarily of ceramides, cholesterol, and FFAs. These lipids form a trilayer long-periodicity phase (LPP) that is unique to this barrier. Knowledge about the LPP is essential in understanding the barrier function. Previous studies of LPP lipid models have identified the position of the major lipid classes and suggested that a large fraction of FFAs and the ceramide acyl chain are present in the central region. However, the precise arrangement, such as lipid subclass mixing (isolated or mixed) and ceramide conformation (extended or hairpin), remains unknown. Here, we deuterated FFAs and the ceramide acyl chain to study CD2 and CH2 interactions with Fourier-transform infrared spectroscopy. The ceramide and FFAs of various chain lengths were not in separate domains but had mixed together. The larger number of CD2-CD2 lipid chain interactions in the LPP than in a symmetrical bilayer structure implied that the ceramide had primarily adopted an extended conformation. Shorter FFAs were present in the central region of the LPP. This model explores the biophysical properties of the stratum corneum's LPP to improve the understanding of the barrier function of this layer.