The lipids of the stratum corneum, particularly the ceramides, are known to play a crucial role for the skin barrier properties. Thereby, the unique ω-acyl ceramide EOS is regarded to be a precondition for the formation of a protective envelope. We report on the chemical synthesis of a new ceramide EOS derivative constituting a saturated and branched ω-acyl chain instead of the naturally occurring ω-esterified linoleic acid moiety, therefore showing an improved stability against oxidative influences. In addition, the thermotropic phase behaviour of the new ceramide was studied using differential scanning calorimetry (DSC) and Fourier transform Raman spectroscopy. The results indicate a phase behaviour similar to the one known for the naturally occurring ceramide EOS. Chain packing behaviour as well as phase transition temperatures are found to be comparable for both ceramide species. Furthermore, the present study addresses the issue of characterising oriented quaternary stratum corneum lipid model membranes based on the new ceramide EOS derivative by means of neutron diffraction. The results indicate the formation of a stable bilayer architecture with membrane parameters comparable to the quaternary model systems containing naturally the occurring ceramide EOS species. Additional molecular dynamics simulations corroborated the findings received from neutron diffraction and the proposed lipid bilayer arrangement.
众所周知,角质层的脂质,尤其是神经酰胺,对皮肤的屏障特性起着至关重要的作用。因此,独特的ω-酰基神经酰胺 EOS 被认为是形成保护膜的先决条件。我们报告了一种新的神经酰胺 EOS 衍
生物的
化学合成,这种衍
生物由饱和支化的 ω-acyl 链代替了天然存在的 ω-esterified linoleic acid 分子,因此具有更好的抗氧化稳定性。此外,还利用差示扫描量热法(
DSC)和傅立叶变换拉曼光谱对新型神经酰胺的热致相行为进行了研究。研究结果表明,这种物质的相行为与已知的天然神经酰胺 EOS 相似。研究发现,这两种神经酰胺的链堆积行为和相变温度具有可比性。此外,本研究还通过中子衍射法研究了基于新型神经酰胺 EOS 衍
生物的定向季角质层脂质模型膜的特征。结果表明形成了稳定的双层结构,其膜参数与含有天然存在的神经酰胺 EOS 种类的四元模型系统相当。额外的分子动力学模拟证实了中子衍射的发现和所提出的脂质双分子层排列。